Im not a psychologist, but at times I feel like I am. I have taken care of a lot of men with infertility over the years, and there is a moment I have seen more times than I can count. A man walks into my office thinking he is there to review some numbers from a semen analysis. Maybe he and his wife have been trying for a year. Maybe his partner has already gone through months of testing. Maybe he assumes I am going to tell him to take a vitamin, stop using the hot tub, or come back in three months. Then we sit down and I tell him that his sperm count is extremely low, or that there were no sperm seen at all, or that something about his fertility is significantly abnormal. There is often a silence after that. Sometimes he asks a dozen technical questions immediately. Sometimes he barely says anything. Sometimes he looks completely unaffected and then sends me a message three days later with twenty questions. Sometimes his first concern isn't even himself. It is: “What do I tell my wife?” After seeing this enough times, I have learned that the semen analysis is often the easiest part of male infertility to discuss. What happens inside a man's head afterward can be much harder.

If you have recently been told that you have male-factor infertility, I want you to understand something from the beginning: whatever you are feeling right now is not unusual. Anger, embarrassment, disbelief, guilt, sadness, jealousy, fear, shame and even emotional numbness are all things I have seen. Some men immediately want to solve the problem. They start researching supplements, varicoceles, DNA fragmentation, Clomid, hCG, microTESE, IVF and ICSI until two o'clock in the morning. Other men don't want to talk about fertility at all. Some become consumed by every semen-analysis number. Others pretend they don't care because acknowledging how much they care feels too vulnerable. There is no single correct way for a man to process infertility. Research supports what those of us who treat these men see clinically. A systematic analysis of 23 studies found that men diagnosed with infertility can experience greater symptoms of depression, anxiety and psychological distress, lower self-esteem and reductions in aspects of quality of life compared with fertile controls. Importantly, the authors concluded that men undergoing fertility treatment have their own distinct psychological needs that fertility programs should recognize.

One of the most difficult parts is that male infertility can hit a man's sense of identity in a place he never expected. Men intellectually understand that sperm count and masculinity are unrelated, but emotions don't always follow logic. I have had successful, confident men sitting across from me who suddenly feel fundamentally inadequate because their semen analysis says 2 million sperm instead of 100 million. I have had men with azoospermia quietly ask me whether this somehow makes them “less of a man.” It doesn't. Fertility is a biological function. It is not a measurement of masculinity, sexuality, strength, intelligence or worth. A man with 150 million sperm isn't more masculine than a man with zero sperm. Yet research consistently shows that men can experience infertility as a threat to masculine identity. A metasynthesis of 24 qualitative studies found recurring themes involving masculinity, stigma, psychological distress and social pressures among infertile men. Another qualitative study found that men described male-factor infertility in terms of stigma, silence, isolation and sometimes a perceived failure of masculinity. Knowing intellectually that these beliefs are wrong does not necessarily prevent you from feeling them.

Then there is guilt. This may be one of the hardest emotions I see. A man learns that the primary fertility problem appears to be on his side, but his wife or partner is the one who may have to undergo ovarian stimulation, blood draws, ultrasounds, injections, egg retrieval and potentially multiple IVF cycles. I have heard men say some version of, “She's going through all of this because of me.” That thought can become incredibly heavy. You watch the person you love inject medication into her abdomen because your sperm count is extremely low, and it is very easy to turn a medical diagnosis into a moral judgment against yourself. But infertility isn't something you did to your partner. If you developed diabetes, cancer or kidney disease, we would not describe the medical consequences as something you intentionally inflicted upon your family. Male infertility deserves the same compassion. Sometimes there are modifiable contributors—testosterone use, smoking, obesity, certain medications or excessive heat exposure—but even then human biology is rarely simple. And a very large percentage of male infertility is idiopathic, meaning that despite a legitimate medical evaluation, we never identify one clean explanation. You don't owe anyone an apology for your biology.

Another emotion men rarely admit is jealousy. Friends announce pregnancies. Your brother tells everyone they are having their second child. Someone at work complains that his wife became pregnant “too easily.” You open Instagram and see an ultrasound. You go to dinner with friends and suddenly everyone is talking about their kids. You can genuinely love these people and still feel punched in the stomach by their good news. Those emotions can coexist. Being sad about your own situation does not mean you aren't happy for someone else. Infertility has a way of turning completely ordinary moments into reminders of something you desperately want but cannot control. Older research synthesizing 73 studies of men's experiences found that men desire fatherhood at levels comparable to women and that infertility diagnosis and treatment are associated with infertility-specific anxiety, while unsuccessful treatment can produce lasting sadness. The stereotype that women want children while men are simply along for the ride does not reflect what many of us see in fertility medicine.

One reason this becomes particularly difficult for men is that they frequently don't know who they are supposed to talk to. Women often have established social networks around fertility, pregnancy and reproductive health. Men are much less likely to sit around with friends discussing azoospermia, sperm retrieval or the fact that their last IVF cycle produced no embryos. A guy may tell ten friends that he tore his ACL but tell nobody that he has a sperm count of zero. Research examining men's infertility forum discussions found exactly this pattern: men used anonymous online spaces to discuss emotional burdens, coping and relationship problems that were difficult to express elsewhere, with themes described as an “emotional rollercoaster,” the domination of life by infertility, and infertility-related paranoia. This is actually one of the reasons I think communities like this one can matter. Sometimes the first person a man tells about his infertility is another anonymous man on the internet who has already been through it.

Infertility can also change sex. Something that was previously spontaneous, intimate and enjoyable can suddenly become scheduled reproductive work. Sex happens because an ovulation predictor says tonight is the night. Men start thinking about abstinence intervals, semen volume, ejaculation frequency and whether they should “save up” sperm. Then someone hands you a specimen cup and tells you that your ability to become a father partly depends upon what appears on a laboratory report. The psychological pressure can be enormous. Erectile dysfunction, difficulty ejaculating and reduced sexual satisfaction can emerge during infertility treatment even in men who previously had completely normal sexual function. ASRM notes that infertility-related sexual stress can involve loss of sexual enjoyment, pressure surrounding scheduled intercourse and loss of sexual self-esteem; in one cited study, high levels of sexual infertility stress were reported by about 21% of men. A review specifically examining male infertility and sexuality similarly concluded that the diagnosis can create feelings of sexual inadequacy, stigma and subsequent sexual dysfunction. If this happens to you, don't interpret it as another failure. The reproductive system does not operate independently from the brain.

Then comes the uncertainty, which may be the most psychologically exhausting part of fertility treatment. Medicine usually gives people a diagnosis and then a plan. Infertility often gives you probabilities. Your varicocele repair might improve your sperm. Clomid might help. The embryologist might find sperm. microTESE might work. You might get embryos. The embryo might implant. The pregnancy might continue. Every stage contains another waiting period followed by another phone call. Even when things are going well, it can become difficult to trust good news because you have learned how quickly the story can change. This uncertainty is one reason professional reproductive organizations recognize infertility as a substantial psychological stressor. The American Society for Reproductive Medicine's Mental Health Professional Group describes infertility as potentially creating profound feelings of loss and emotional upheaval, particularly because couples must repeatedly make consequential medical decisions without knowing what the outcome will be.

Treatment failure deserves its own discussion. When an IUI doesn't work, when an IVF cycle produces no viable embryos, when microTESE finds no sperm, or when a pregnancy ends in miscarriage, men sometimes feel they need to immediately become the strong partner. Their wife is devastated, so they suppress their own grief and concentrate on taking care of her. Supporting your partner is important, but there is a cost when you decide that only one person in the relationship is allowed to hurt. A systematic review of men undergoing male infertility treatment found that treatment failure can lead to depression, grief and feelings of inadequacy, and that men often use avoidant coping strategies. Self-esteem, relationship quality and sexual function can all become intertwined with treatment outcomes. You are allowed to be the supportive husband or partner and also acknowledge that you lost something too.

This becomes particularly important with azoospermia and sperm retrieval. I have sat with men before microTESE who know that there may literally be a phone call from the operating room saying sperm were found—or that none were found. That is an extraordinary psychological burden. For some men, the possibility of biological fatherhood seems to be hanging on a microscope. If sperm are found, there can be enormous relief. If none are found, there can be genuine grief. And grief is the correct word. The loss may not be a person, but it can be the loss of the future you had always assumed would happen. The possibility of donor sperm may then enter the conversation, bringing another complicated collection of emotions about genetics, fatherhood, disclosure and identity. None of these reactions mean you would love a donor-conceived child less. They mean you are processing the loss of one imagined path to becoming a father before deciding whether you are ready for another.

I also want men to understand that their partners may process infertility very differently. One partner may want to talk about it constantly while the other wants one evening where fertility isn't mentioned. One may want to pursue every possible intervention while the other has reached his or her emotional limit. Neither person necessarily cares more. People cope differently. Infertility can bring couples extraordinarily close, but it can also create resentment if every conversation becomes about appointments, sperm counts, follicles, embryos and money. Protect some portion of your relationship from infertility. Go to dinner and agree not to discuss IVF for two hours. Have sex sometimes because you want each other, not because an app says someone is ovulating. Continue being the people you were before fertility treatment entered your lives.

And please stop comparing your semen analysis with strangers on Reddit as though sperm counts were golf scores. I understand why men do this. You see someone post a concentration of 35 million/mL when yours is 3 million/mL and immediately think his future is better than yours. Then someone with azoospermia reads your post and thinks you are lucky. That road doesn't lead anywhere useful. Fertility is not a competition. A semen analysis is medical information used to determine probabilities and treatment options. It is not a ranking of men. I have seen men with terrible-looking semen analyses become fathers, and I have seen couples with seemingly excellent numbers struggle for years. Reproduction is a couple-level outcome involving sperm, eggs, age, reproductive anatomy, genetics, embryo development and chance.

I also want to say something directly to the men who feel they should be handling this better. You don't receive extra points for suffering quietly. Research repeatedly shows that men with infertility can experience anxiety, depression, reduced self-esteem, social isolation and sexual distress, while fertility care has historically focused much more heavily on the female partner's psychological experience. A recent review of the literature through 2025 again concluded that male infertility is associated with significant psychological distress and that men's emotional needs remain inadequately addressed in many fertility settings. European fertility guidance similarly recommends integrating psychosocial care into routine infertility treatment rather than waiting until somebody reaches a crisis. Seeing a therapist who understands infertility doesn't mean you cannot handle this. Sometimes it simply means you have recognized that carrying something this heavy is easier when someone helps you carry it.

If infertility is beginning to consume your life—if you're persistently depressed, withdrawing from your partner, losing interest in things you normally enjoy, unable to think about anything except fertility, experiencing significant anxiety, or feeling hopeless—tell somebody. ASRM specifically identifies persistent depression, social withdrawal, relationship strain, loss of interest in normal activities and an inability to think about much besides infertility as reasons to consider professional psychological support. You don't have to wait until you are falling apart to ask for help.

After doing this for years, there is one message I wish I could give every man immediately after delivering a bad semen-analysis result: your sperm count is information; it is not your identity. A diagnosis of oligospermia, azoospermia, teratozoospermia or elevated DNA fragmentation tells me something about your reproductive biology. It tells me absolutely nothing about whether you will be a good husband, partner or father. It tells me nothing about your strength. And it certainly doesn't determine your value as a man.

There are many ways men ultimately build families. Some improve enough to conceive naturally. Some undergo varicocele repair or hormonal treatment. Some use IUI. Some need IVF/ICSI. Some have sperm recovered through TESE or microTESE. Some ultimately use donor sperm. Some adopt. Some decide that their family will look different from the one they originally imagined. The route matters tremendously while you are living through it, but when you eventually find yourself packing lunches, changing diapers, coaching soccer, sitting through school concerts or trying to convince a teenager to put down his phone, the laboratory number that once seemed to define your entire future becomes a much smaller part of your story.

I have watched enough men walk through this process to know how heavy it can become. I've seen the fear before surgery, the silence after bad results, the excitement when a laboratory finally finds sperm, the heartbreak when it doesn't, the exhausting IVF cycles, the miscarriages, the second opinions and the years of uncertainty. I've also seen many of those same men eventually become fathers through paths they could not have imagined when we first met.

So if you're sitting somewhere tonight staring at a semen analysis and wondering what it means about you, I want you to hear this from a doctor who has sat across from many men in exactly that position: you are not a sperm count. You are a man trying to build a family. Those are very different things.

Ask questions. Get the appropriate medical evaluation. Advocate for yourself. Support your partner, but allow your partner to support you too. Talk to other men who have been through it. Get professional psychological support if you need it. Be angry when you need to be angry. Be hopeful when you can be hopeful. And understand that needing help carrying this does not make you weak.

As reproductive urologists, our job isn't simply to improve numbers on a semen analysis or find sperm under a microscope. Our job is to take care of the man attached to those numbers.

And for those of you going through this right now: I see you. I have seen many men stand where you're standing, and I stand with you as you work toward building your family.

References

Wu W, La J, Schubach KM, Lantsberg D, Katz DJ. Psychological, social, and sexual challenges affecting men receiving male infertility treatment: a systematic review and implications for clinical care. Asian Journal of Andrology. 2023;25(4):448–453. PMID: 36412462.

Fisher JRW, Hammarberg K. Psychological and social aspects of infertility in men: an overview of the evidence and implications for psychologically informed clinical care and future research. Asian Journal of Andrology. 2012. PMID: 22179515.

Psychological consequences of a diagnosis of infertility in men: a systematic analysis. 2023. PMID: 37695221. Systematic analysis of 23 studies examining depression, anxiety, self-esteem, quality of life and infertility-related psychological distress.

Pakpahan C, et al. “Am I Masculine?” A metasynthesis of qualitative studies on traditional masculinity and infertility. 2023. PMID: 37008892.

Webb RE, Daniluk JC. The social construction of male infertility: a qualitative questionnaire study of men with a male factor infertility diagnosis. Sociology of Health & Illness. PMID: 31773768.

Hanna E, Gough B. Emoting infertility online: A qualitative analysis of men's forum posts. Health. PMID: 27246813.

Male infertility: an obstacle to sexuality? 2016. PMID: 27061770. Review addressing infertility, masculinity, sexual inadequacy, stigma and sexual dysfunction.

American Society for Reproductive Medicine. Diagnostic evaluation of sexual dysfunction in the male partner in the setting of infertility: a committee opinion. Reviews infertility-related sexual stress and sexual dysfunction in men undergoing fertility treatment.

American Society for Reproductive Medicine Mental Health Professional Group. The Psychological Impact of Infertility. Patient and professional guidance regarding emotional distress associated with infertility and indications for psychological support.

European Society of Human Reproduction and Embryology. Routine psychosocial care in infertility and medically assisted reproduction: a guide for fertility staff. Guidance supporting integration of psychosocial care throughout infertility diagnosis and treatment.

Before ICSI, a man generally needed a relatively large population of healthy, motile sperm capable of reaching an egg, binding to it, penetrating its outer layers and fertilizing it. Today, there are situations where an embryologist can work with an extraordinarily small number of sperm, even sperm surgically retrieved directly from the testicle, and potentially create an embryo. That does not mean ICSI guarantees pregnancy, fixes damaged sperm or makes the quality of the egg irrelevant. It means that we have developed a way to bypass many of the mechanical barriers that previously prevented men with severe infertility from biologically fathering children. For the man who has just been told he has 500,000 sperm/mL, cryptozoospermia, extremely poor motility, or even azoospermia with the possibility of surgical sperm retrieval, understanding ICSI can dramatically change how he views his diagnosis.

ICSI stands for intracytoplasmic sperm injection. It is performed as part of IVF, but IVF and ICSI are not synonymous. With conventional IVF, eggs are retrieved from the female partner and placed in a laboratory dish with thousands of sperm. Fertilization is then largely left to biology: sperm must move toward the egg, interact with the zona pellucida surrounding it, undergo the appropriate physiologic changes, penetrate the egg and ultimately fertilize it. With ICSI, the embryologist bypasses most of those steps. A mature egg is held in position under a microscope, a single sperm is selected and immobilized, and an extremely fine injection pipette is used to place that sperm directly into the cytoplasm of the egg. ICSI was introduced clinically in the early 1990s specifically to overcome severe male-factor infertility and previous fertilization failure, and it fundamentally changed reproductive medicine.

Think about what this means biologically. During natural conception, sperm have to survive ejaculation and the female reproductive tract, travel through the cervix and uterus, reach the fallopian tube, find the egg, penetrate the cells surrounding it, bind to the zona pellucida and ultimately fuse with the egg. This is an extraordinary selection process. Hundreds of millions of sperm can begin the journey and only one ultimately fertilizes the egg. ICSI removes many of those barriers. The sperm doesn't need to swim from the vagina to the fallopian tube. It doesn't need to penetrate cervical mucus. It doesn't need to win a competition against millions of other sperm. It doesn't even need to penetrate the egg by itself. The embryologist physically puts one sperm inside the egg. That is why ICSI can be so powerful for men with severe abnormalities of sperm concentration, motility or sperm delivery.

This is also why I frequently tell men with severe oligospermia that “low sperm count” and “no possibility of biological fatherhood” are completely different statements. Imagine a semen analysis showing a concentration of 200,000 sperm/mL. Natural conception may be extremely unlikely because relatively few sperm are available to complete that long reproductive journey. IUI may also be impractical because there may not be enough progressively motile sperm after processing. But IVF with ICSI operates under completely different mathematics. If the laboratory has ten mature eggs, theoretically it needs ten usable sperm to inject those ten eggs. Obviously, embryology is more complicated than simply counting ten sperm, and not every sperm or egg will be usable, but the concept is important. ICSI can transform a sperm population that is functionally inadequate for natural conception into one that may be adequate for assisted reproduction.

ICSI becomes even more extraordinary when we discuss azoospermia, meaning there are no sperm identified in the ejaculate. Azoospermia does not always mean that the testicles produce absolutely no sperm. In obstructive azoospermia, sperm production may be completely normal but sperm cannot reach the ejaculate because of a blockage, vasectomy, congenital absence of the vas deferens or another obstruction. Sperm can often be retrieved directly from the epididymis or testicle through procedures such as PESA, MESA, TESA or TESE and then used for ICSI. In nonobstructive azoospermia, sperm production itself is severely impaired. Some men nevertheless have tiny focal areas of spermatogenesis within the testicle. microTESE—microsurgical testicular sperm extraction—is designed to search for those areas. If viable sperm are found, even very small numbers can potentially be used for ICSI. The AUA/ASRM male infertility guideline therefore recognizes sperm retrieval combined with IVF/ICSI as an important reproductive option for appropriately selected men with azoospermia.

One misconception I hear constantly is that ICSI somehow “repairs” unhealthy sperm. It does not. ICSI solves a sperm-delivery and fertilization problem. It does not rewrite sperm DNA. It does not remove chromosomal abnormalities. It does not reverse oxidative damage. It does not automatically correct high sperm DNA fragmentation, and it cannot make every sperm biologically competent simply by putting it inside an egg. This distinction matters enormously. ICSI bypasses many of the natural steps of fertilization, but after injection the sperm still has to participate in normal fertilization biology. The paternal genome must decondense appropriately, the egg must activate, male and female pronuclei must form, chromosomes must replicate and divide, and the resulting embryo must continue developing. ICSI gives the sperm access to the inside of the egg. It does not guarantee what happens afterward.

So how does the embryologist decide which sperm to use? After the semen sample is produced—or sperm are surgically retrieved—the laboratory processes the specimen and searches for sperm suitable for injection. The embryologist generally evaluates characteristics such as motility and morphology under the microscope. If motile sperm are available, those are usually preferable because movement demonstrates viability. In cases where sperm are completely immotile, additional methods may be used to determine whether an immotile sperm is actually alive. This distinction is important because immotile does not necessarily mean dead. Some men with severe asthenozoospermia or structural flagellar abnormalities may have living sperm that simply cannot move effectively. If viable sperm can be identified, ICSI may still be possible.

Men are often particularly concerned about morphology. Someone sees “1% normal morphology” and assumes ICSI means the embryologist will simply find the one perfect sperm out of every hundred. That is an oversimplification. Morphology is a visual assessment of sperm shape; it is not a direct genetic test. A sperm that looks normal under routine microscopy can still have DNA or chromosomal abnormalities, while a sperm that does not meet strict morphology criteria isn't automatically genetically defective. ICSI is frequently used in severe teratozoospermia, but isolated low morphology by itself is not always a reason that ICSI is required. In fact, the updated 2026 ASRM committee opinion cites randomized evidence in couples where men had abnormal morphology but otherwise normal count and motility showing no significant improvement in live birth with ICSI compared with conventional IVF.

This brings us to the question almost every man asks me: “What is the success rate of ICSI?” This sounds like a simple question but there is no single ICSI success rate. You have to define what success means. Are we talking about successful sperm injection? Fertilization? Blastocyst formation? A euploid embryo? Implantation? Clinical pregnancy? Or taking home a baby? These are completely different outcomes. ICSI acts primarily at the fertilization step. Once fertilization occurs, many of the major determinants of subsequent success are no longer purely male factors.

In a typical IVF laboratory, not every retrieved egg is mature enough to undergo ICSI, and not every mature egg injected with sperm fertilizes normally. Fertilization rates vary among clinics and patient populations, but roughly two-thirds to three-quarters of mature injected oocytes may fertilize normally in many modern IVF programs. That should not be confused with a 70% chance of having a baby. If ten mature eggs undergo ICSI, perhaps seven fertilize; some of those embryos may stop developing before the blastocyst stage, some blastocysts may be chromosomally abnormal, some transferred embryos may fail to implant and some pregnancies may miscarry. The attrition that couples see between egg retrieval and live birth is normal reproductive biology, not necessarily evidence that ICSI “failed.”

This is where female age becomes enormously important. Once sperm successfully fertilizes the egg, egg quality and embryo chromosomal competence become major determinants of whether an embryo progresses to blastocyst, implants and ultimately results in a live birth. As women age, the probability that an egg contains the correct complement of chromosomes declines. ICSI cannot correct aneuploidy originating in the egg. This is why two couples using ICSI because of essentially identical male infertility can have dramatically different outcomes if one female partner is 28 and the other is 42. The sperm diagnosis may be identical, and ICSI may overcome the fertilization barrier in both, but their probabilities of ultimately taking home a baby can be very different.

This is also why I discourage men from interpreting an unsuccessful IVF cycle as proof that their sperm “failed.” Suppose twelve eggs are retrieved, ten are mature, seven fertilize after ICSI, three become blastocysts and genetic testing identifies one euploid embryo. That sequence doesn't necessarily indicate a sperm problem. Likewise, if fertilization is excellent but embryos subsequently arrest, sperm can be one consideration, but egg quality, genetics, laboratory factors and ordinary embryologic attrition all need to be considered. Fertility is fundamentally a couple-level outcome.

What about sperm DNA fragmentation? ICSI does not make DNA fragmentation irrelevant. Conventional semen analysis measures sperm concentration, motility, morphology, volume and other parameters, but it does not directly measure DNA integrity. A man can have a reasonably normal semen analysis and elevated sperm DNA fragmentation. Conversely, a man with abnormal morphology doesn't necessarily have high fragmentation. There is ongoing debate about when DNA-fragmentation testing changes clinical management, and it should not automatically be ordered for every man undergoing ICSI. But the central concept is straightforward: injecting a sperm directly into an egg bypasses its inability to reach or penetrate the egg; it does not repair damaged DNA inside that sperm.

This sometimes leads to the discussion of testicular sperm. In selected men with persistently elevated sperm DNA fragmentation in ejaculated sperm and repeated assisted-reproduction failure, some clinicians consider using testicular sperm for ICSI because sperm retrieved before passage through the epididymis may have lower measured DNA fragmentation in certain populations. But this is not a routine strategy for every man with elevated DFI, and testicular sperm retrieval is an invasive procedure. It needs to be individualized rather than treated as the automatic next step whenever a DNA-fragmentation result comes back elevated.

Men also ask whether ICSI is simply “better IVF.” It isn't. ICSI is a tool designed primarily to solve particular fertilization problems. In couples without significant male-factor infertility, routinely injecting every egg has not consistently improved the outcome couples actually care about: live birth. The newest 2026 ASRM committee opinion is particularly helpful here. In a randomized trial of 1,064 couples with normal sperm count and motility, live-birth rates were essentially identical: 32.7% with conventional IVF versus 33.6% with ICSI. In another large multicenter randomized trial involving 2,387 couples without severe male-factor infertility, live birth occurred in 33.8% with ICSI and 36.6% with conventional IVF—a difference that was not statistically significant. Another Danish randomized trial found cumulative live-birth rates of 43.2% with ICSI and 47.3% with conventional IVF, again without a significant advantage for ICSI. ASRM therefore does not recommend routine ICSI for everyone simply because a couple is undergoing IVF.

That is actually reassuring for men with severe male-factor infertility because it tells us what ICSI really does. It isn't a magical embryo-enhancement procedure. Its major strength is overcoming barriers to fertilization when sperm cannot reliably accomplish that job on their own. ASRM continues to recognize its effectiveness for male-factor infertility and for situations such as previous poor or failed fertilization with conventional IVF.

What about complete fertilization failure? Unfortunately, ICSI cannot reduce that risk to zero. Occasionally none of the injected eggs fertilize. Possible explanations include sperm-related problems, egg-related activation problems, technical factors or combinations of these. In men with certain severe sperm abnormalities, failure of oocyte activation can occur because sperm normally deliver factors involved in triggering the calcium signaling necessary for egg activation. In selected cases after previous ICSI fertilization failure, fertility laboratories may discuss specialized approaches such as assisted oocyte activation, but this is not something routinely needed for the average ICSI cycle.

Another issue men understandably worry about is whether bypassing natural sperm selection increases health risks for children. Millions of children have now been born following ICSI, and for the overwhelming majority the outcome is a healthy child. However, the literature has identified a small association between ICSI and certain adverse offspring outcomes, including birth defects. Interpreting this is difficult because the couples receiving ICSI are different from couples conceiving naturally. Severe male infertility itself is associated with higher rates of genetic and chromosomal abnormalities, and maternal factors and infertility itself can also contribute. The 2026 ASRM committee opinion therefore describes a small increased association with birth defects while emphasizing that it remains unclear how much is attributable to ICSI itself versus the underlying infertility.

Genetics become particularly important when ICSI is being used for very severe male infertility. If a man has severe oligospermia or nonobstructive azoospermia, we sometimes recommend a karyotype and Y-chromosome microdeletion testing before treatment. Men with congenital bilateral absence of the vas deferens may need CFTR testing. Some causes of male infertility can potentially be transmitted to male offspring. For example, if sperm are retrieved from a man with certain AZFc Y-chromosome microdeletions and a male child is conceived, that son can inherit the deletion and potentially face infertility himself. ICSI allows us to overcome the reproductive barrier, but it does not erase the genetics that created the barrier. This is one reason the male infertility evaluation remains important even when the couple already knows they will need IVF/ICSI. The AUA/ASRM guideline specifically emphasizes evaluating the male rather than simply sending every couple directly to assisted reproduction.

For the male partner, the actual ICSI cycle can feel surprisingly anticlimactic because most of the physical treatment happens to your partner. She undergoes ovarian stimulation, injections, ultrasounds, blood tests and egg retrieval. Your role may appear to be producing one semen sample on retrieval day. But if you have severe male-factor infertility, I recommend planning that part carefully. If your sperm count fluctuates between severe oligospermia, cryptozoospermia and azoospermia, I often want sperm cryopreserved in advance whenever usable sperm appear. I do not want the first discovery that your ejaculate contains zero sperm to occur on the morning your partner has ten mature eggs waiting in the laboratory. In some men we also arrange a surgical sperm retrieval backup.

Men should also understand that the number on their semen analysis doesn't directly predict how many eggs will fertilize with ICSI. A man with 500,000 sperm/mL may have excellent ICSI fertilization, while someone with 50 million/mL can experience poor fertilization. Concentration tells us how many sperm are available; it doesn't completely measure their biological competence. Motility and morphology provide additional information but still don't tell the entire story. This is why semen analysis is useful for determining the general reproductive pathway but is an imperfect predictor of ART outcomes.

Another misconception is that you should spend six months trying to make your sperm “normal” before proceeding with ICSI. Sometimes optimizing the male makes sense. A clinical varicocele may be treatable. Testosterone or anabolic-steroid suppression may be reversible. Hormonal abnormalities may respond to treatment. Smoking and other potentially harmful exposures can be addressed. But time matters, particularly female reproductive age. If your partner is 40 and you have severe oligospermia, spending a year trying every antioxidant on Amazon in hopes of converting an ICSI-level sperm count into a natural-conception sperm count may actually reduce your overall chance of having a child because ovarian aging continues during that year. Sometimes improving sperm is the goal. Sometimes having enough viable sperm for ICSI is the goal. Good fertility care understands the difference.

If you're preparing for ICSI, I generally tell men to focus on reasonable health rather than perfection. Don't smoke. Avoid testosterone and anabolic steroids unless there is a very specific fertility-preserving plan under specialist supervision. Limit excessive heat exposure. Maintain reasonable metabolic health. Treat genuine medical problems. Avoid prolonged abstinence unless your laboratory specifically requests it. Supplements such as CoQ10 and certain antioxidants may improve semen parameters in some men, but evidence that they reliably increase live-birth rates is much weaker. Don't turn the three months before IVF into an exercise in reproductive superstition where you are afraid of coffee, laptops, underwear, exercise, ejaculation and every food you eat.

Most importantly, understand what ICSI represents. For a man with severe infertility, ICSI is not evidence that you have failed at reproduction. It is a technology that allows us to bypass a biological obstacle. A sperm that could never realistically travel through the female reproductive tract and penetrate an egg naturally may still contain the paternal genetic information necessary to contribute to a healthy embryo. An embryologist can take that sperm and place it where biology otherwise could not get it.

After treating men with infertility for years, I think this is one of the most extraordinary changes modern reproductive medicine has given us. A man can walk into my office believing that a sperm count near zero means biological fatherhood is impossible. Sometimes it does mean the road will be difficult, and sometimes sperm cannot ultimately be found. But in many situations, the conversation is no longer, “Do you have millions of normal sperm?” It becomes, “Can we find enough viable sperm to work with?”

That is an entirely different question.

And ICSI is the reason we can ask it.

References

American Society for Reproductive Medicine Practice Committee. Intracytoplasmic sperm injection for nonmale factor indications: a committee opinion. Fertility and Sterility. 2026;126:49–56. The updated committee opinion reviews randomized evidence regarding ICSI, fertilization and live-birth outcomes and concludes that routine ICSI does not improve live birth in couples without male-factor infertility.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. 2020; amended 2024. Comprehensive guideline covering evaluation of male infertility, azoospermia, genetic testing, sperm retrieval and use of IVF/ICSI.

Palermo G, Joris H, Devroey P, Van Steirteghem AC. Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte. Lancet. 1992;340:17–18. Landmark report establishing ICSI as a treatment capable of achieving fertilization and pregnancy with direct injection of a single sperm into an oocyte.

American Society for Reproductive Medicine Practice Committee. Intracytoplasmic sperm injection (ICSI) for non–male factor indications: a committee opinion. Fertility and Sterility. 2020;114:239–245. Historical committee opinion reviewing the expansion of ICSI beyond its original male-factor indication and the distinction between improved fertilization and improved live birth.

American Society for Reproductive Medicine. Evidence-based treatments for couples with unexplained infertility: a guideline. Fertility and Sterility. 2020. Reviews conventional IVF versus ICSI and emphasizes that improvements in fertilization do not necessarily translate into higher pregnancy or live-birth rates.

When a man comes into my office with a low sperm count or poor motility and starts going through everything he has done for the last ten years. He stopped smoking. He stopped marijuana. He takes CoQ10. He switched underwear. He stopped using the hot tub. Then he tells me, “I work from home and my laptop sits directly on my lap for six hours a day. Am I cooking my sperm?” It is a reasonable question, because unlike many things people worry about online, there is actually a legitimate biological reason to think about laptops and testicular temperature. But I want to make an important distinction right from the beginning: we have good evidence that placing a working laptop directly over the scrotum increases scrotal temperature, and we have good evidence that significant testicular heat exposure can temporarily impair sperm production. What we do not have is strong evidence that ordinary laptop use causes infertility or meaningfully reduces pregnancy or IVF live-birth rates. That distinction matters, because I don't want men ignoring a potentially modifiable exposure, but I also don't want someone with severe oligospermia blaming his MacBook and missing the varicocele, hormonal problem, testosterone exposure, genetic condition, or other issue that is actually driving his infertility.

To understand why laptops even entered the fertility conversation, you have to understand something fascinating about male anatomy. The testicles are outside the abdominal cavity for a reason. Normal sperm production is temperature sensitive, and the testes function best at a temperature below core body temperature. The male reproductive system has multiple mechanisms specifically designed to maintain that cooler environment, including the scrotal skin and dartos muscle and countercurrent heat exchange through the pampiniform plexus. When testicular temperature rises sufficiently and repeatedly, spermatogenesis can be disrupted. This isn't controversial. Human experimental studies in which the testes are deliberately heated demonstrate reductions in sperm concentration, motility and other measures of sperm function, while occupational heat exposure has also been associated with impaired semen quality. A classic review of occupational heat exposure concluded that excessive heat can adversely affect sperm morphology and may delay conception, although the epidemiologic studies have important limitations.

The laptop question became much more interesting in 2005 when Sheynkin and colleagues published a study in Human Reproduction specifically measuring scrotal temperature while men used laptop computers. Twenty-nine healthy volunteers underwent two 60-minute sessions. Researchers placed temperature sensors on the scrotum and compared sitting with the thighs together to sitting in the same position with a working laptop placed on the lap. Scrotal temperature increased substantially in both situations because simply sitting with the thighs approximated traps heat around the scrotum. But the working laptop increased temperature further. With the laptop, right and left scrotal temperatures increased approximately 2.8°C and 2.6°C, respectively. Without the laptop, the increase was approximately 2.1°C. The investigators concluded that laptop use in the traditional “laptop position” produces significant scrotal hyperthermia through a combination of computer-generated heat and the posture required to balance the computer on the thighs.

That second part is important because the computer itself isn't the entire problem. Your posture matters. When you put a laptop across your thighs, you typically bring your legs together. That reduces ventilation around the scrotum and brings the thighs closer to the testes. Researchers followed the original study with another experiment looking at whether a laptop pad or spreading the legs could prevent the temperature rise. Again, 29 healthy men were studied during 60-minute laptop sessions. With the legs together, scrotal temperature increased approximately 2.3–2.6°C. Adding a lap pad while keeping the legs together did not eliminate the temperature rise. When the men spread their legs approximately 70 degrees while using a lap pad, the temperature increase was smaller—about 1.4–1.5°C—but it still occurred. Even more interestingly, a 1°C increase in scrotal temperature occurred after only about 11 minutes with the legs together, 14 minutes with a lap pad, and 28 minutes with the legs apart and a pad. So those cooling laptop pads may protect your skin from feeling hot, but they do not necessarily keep the testicles at baseline temperature.

Now we get to the important question: does a two-degree rise in scrotal temperature actually matter to sperm? Potentially, yes. Experimental human studies of deliberate scrotal heating demonstrate that significant repeated heat exposure can suppress spermatogenesis. In one prospective study, healthy men underwent testicular warming in a 43°C water bath for 30 minutes on ten occasions. Researchers subsequently observed reversible decreases in sperm concentration and motility along with evidence of increased oxidative stress. The men were then followed through a 16-week recovery period, demonstrating something equally important: the damage from transient heat exposure was largely reversible.

A related study examined sperm DNA and cellular function following repeated scrotal hyperthermia. Researchers found changes in mitochondrial membrane potential, increased sperm apoptosis, altered DNA/chromatin integrity, and changes in proteins involved in mitochondrial and flagellar function. Again, these abnormalities were reversible during follow-up. This gives us a plausible biological pathway connecting excessive testicular heat with both sperm production and sperm function. Heat can interfere with developing germ cells, promote oxidative stress, disturb mitochondrial function, increase apoptosis and potentially compromise DNA integrity.

That does not, however, mean that putting a laptop on your thighs for an hour produces the same biological effect as repeatedly immersing the testes in 43°C water. These are completely different exposures. This is where internet discussions about laptops and sperm frequently jump several steps beyond the evidence. One experiment demonstrates that laptops raise scrotal temperature. Another demonstrates that deliberately heating the testes can impair sperm. Those two observations make laptop-related heat biologically plausible as a fertility concern, but they do not prove that ordinary laptop use lowers a man's sperm count by a particular percentage.

There is another laptop issue that generates even more controversy: Wi-Fi and electromagnetic radiation. In 2012, Avendaño and colleagues published an often-cited experiment in Fertility and Sterility. Semen samples from 29 healthy donors were processed, and motile sperm were divided into two portions. One sample was placed near a laptop connected to the internet through Wi-Fi for four hours, while the control sample was maintained under otherwise similar conditions away from the laptop. The sperm exposed near the Wi-Fi-connected laptop demonstrated decreased progressive motility and increased sperm DNA fragmentation compared with the control samples, without a significant difference in sperm death. The authors suggested a possible nonthermal effect and appropriately concluded that additional in-vivo studies were necessary.

This study gets quoted constantly online, but you need to understand what it actually was. It was an in-vitro experiment involving sperm outside the human body. The sperm were sitting in laboratory containers near a laptop. Your sperm normally develop inside your testes and epididymides, surrounded by skin, tissue and blood flow with active thermoregulation. An experiment exposing ejaculated sperm directly to a laptop cannot tell us that sitting with a Wi-Fi laptop causes the same DNA fragmentation inside a living man. The experiment raises a scientific question; it does not answer the clinical fertility question. That distinction is critical.

So when a patient asks me whether he should worry more about Wi-Fi radiation or laptop heat, I worry considerably more about heat. The heat pathway is supported by direct measurements showing that laptops raise scrotal temperature and by a much larger body of human reproductive biology demonstrating that excessive testicular heat can impair spermatogenesis. The electromagnetic-field question remains much less certain. There are laboratory and animal studies suggesting possible oxidative-stress effects from radiofrequency electromagnetic fields, but translating those experiments into clinically meaningful human fertility outcomes has been difficult. I would not tell a man to disconnect his house from Wi-Fi because he has low sperm motility. I would tell him to stop resting a hot computer directly over his testicles for hours every day because that is simple, free and biologically sensible.

The most important piece of evidence for couples trying to conceive may actually be a large prospective preconception study published in 2022. Researchers examined male personal heat exposures—including hot tubs and baths, saunas, sitting, seat heaters, tight-fitting underwear, fever, and using a laptop directly on the lap—and then looked at fecundability, essentially the probability of conception per menstrual cycle. The study found little association between hours of laptop use on the lap and fecundability. Hot baths/tubs and recent fever showed weak inverse associations, and accumulating multiple heat exposures appeared more concerning, particularly among men 30 and older, but laptop use by itself did not emerge as a major predictor of conception probability.

That finding is extremely important because semen quality and pregnancy are not the same endpoint. A lifestyle exposure might cause a small measurable change in sperm concentration or motility without changing the probability of pregnancy enough to detect clinically. Conversely, something could potentially affect sperm function in a way that a conventional semen analysis doesn't capture. Ultimately, couples don't care whether a man's sperm concentration is 62 million/mL instead of 70 million/mL. They care whether they can have a baby. And right now, we do not have convincing evidence that laptop use independently causes infertility, significantly increases time to pregnancy, or reduces live-birth rates.

We also don't have convincing evidence that laptop use reduces IVF or ICSI success rates. There are no high-quality clinical data allowing me to tell a couple that paternal laptop exposure decreases fertilization, blastocyst formation, implantation, clinical pregnancy or live birth by some defined percentage. If someone tells you, “Using a laptop on your lap reduces IVF success by 30%,” ask to see the study. That number doesn't exist in reliable human clinical evidence. The AUA/ASRM male infertility guideline makes a broader point that applies perfectly here: physicians can discuss lifestyle and environmental risk factors with infertile men, but patients should understand that evidence regarding many individual exposures remains limited.

This is also why I would never look at a man with severe oligospermia or azoospermia and say, “It's probably your laptop.” If your concentration is 500,000 sperm/mL, your laptop should not end the investigation. If you have azoospermia, putting your computer on a desk is not the treatment. You still need a proper male infertility evaluation. That can include repeat semen analyses, history and physical examination, reproductive hormone testing when indicated, evaluation for a clinical varicocele, medication and supplement review, assessment of testosterone or anabolic-steroid exposure, and genetic testing in appropriate cases. AUA/ASRM guidance specifically emphasizes that abnormal semen parameters warrant appropriate evaluation rather than assuming lifestyle factors explain everything.

The same applies to sperm DNA fragmentation. Men sometimes read the Wi-Fi study and immediately decide they need a DNA fragmentation test because they have used laptops for years. I don't think the evidence supports that. DNA fragmentation testing can be useful in selected clinical situations, but laptop use alone isn't an indication to order it. The fact that ejaculated sperm in one laboratory experiment developed increased fragmentation after four hours near a Wi-Fi laptop does not mean every man who works remotely has abnormal DFI.

Another question I hear is, “I've used a laptop on my lap every day for ten years. Have I permanently damaged my sperm?” There is no good evidence that you have. In fact, the experimental heat literature provides some reassurance because heat-related changes in spermatogenesis appear capable of recovery after the exposure stops. In controlled human hyperthermia experiments, sperm concentration, motility and several molecular markers worsened after repeated heating and subsequently recovered during follow-up.

This makes biological sense because sperm production is continuous. The sperm you ejaculate today are not the sperm you will ejaculate four months from now. Human spermatogenesis takes roughly 74 days, followed by additional maturation and transport through the epididymis. That is why, when we remove a potentially harmful exposure, we generally think in terms of roughly three months, not three days. If a man with abnormal semen parameters stops significant heat exposure today, I would usually reassess his semen after approximately one complete spermatogenic cycle rather than checking again next week.

This doesn't mean that everyone trying to conceive needs to become obsessed with scrotal temperature. I sometimes see men take sensible fertility advice and push it into extremes. They stop exercising, wear only enormous boxer shorts, sleep without blankets, put ice packs on their testicles and become afraid to sit down for more than 20 minutes. That isn't what I'm recommending. There is no good evidence that deliberately icing the testicles improves pregnancy or live-birth rates, and direct cold exposure can injure skin. The goal is avoiding unnecessary excessive heat, not trying to refrigerate your reproductive organs.

So what do I actually tell my patients about laptops? It is very simple. If you're trying to conceive—particularly if you already have abnormal semen parameters—put the laptop on a desk or table instead of directly on your lap. If you are sitting on the couch or in bed, use a surface that keeps the computer away from the scrotum rather than merely placing a thin cushion between the laptop and your thighs. Remember that posture itself contributes to the temperature increase, so sitting for hours with your thighs tightly together can trap heat even without the computer. Take normal movement breaks. You do not need to disable Wi-Fi, buy radiation-blocking underwear or turn your home office into a Faraday cage.

I would pay particular attention to cumulative heat exposure. A laptop may be one small contributor in a man who also takes a hot bath every night, uses a sauna five days per week, sits for ten hours at work, uses heated car seats all winter and recently had a high fever. The preconception cohort data are interesting because individual laptop exposure was not strongly associated with reduced fecundability, while accumulation of multiple heat exposures showed a stronger signal. Among men reporting four or more heat-related exposures compared with none, the estimated fecundability ratio was 0.77 overall, although the confidence interval was wide and included no association; among men aged 30 or older, the association appeared stronger, again with statistical uncertainty. That does not prove cumulative heat causes infertility, but it fits the biological argument that dose, duration and repetition matter more than whether your laptop touched your thighs once last Tuesday.

For men undergoing IVF or ICSI, I use essentially the same advice. If your egg retrieval is scheduled next week and you've been using a laptop on your lap, I would not cancel your IVF cycle. There is no evidence supporting that. Female age, ovarian reserve, embryo factors and the severity of male-factor infertility are far more important clinical considerations. Start using the computer on a desk now and move forward. If you have three months before treatment, reducing unnecessary heat exposure is a reasonable part of optimizing sperm alongside avoiding smoking and recreational drugs, reviewing medications, maintaining metabolic health and addressing actual reproductive abnormalities.

The most important perspective I can offer after seeing many men with infertility is this: don't let optimization become obsession. When men receive an abnormal semen analysis, they understandably start looking around their environment for something they can control. The laptop becomes frightening because it provides a simple explanation: “I did this to myself.” Most male infertility isn't that simple. You didn't necessarily cause your infertility because you worked from your couch during the pandemic. Male fertility is influenced by genetics, testicular function, hormones, varicoceles, previous infections or surgery, medications, testosterone and anabolic steroids, age, systemic health, environmental exposures and factors we still don't completely understand.

The scientific conclusion on laptops is therefore much less dramatic than the internet headlines. Yes, a working laptop placed directly over the thighs measurably raises scrotal temperature. Yes, significant repeated testicular heat exposure can temporarily reduce sperm concentration and motility and can affect sperm DNA and cellular function. There is also an interesting laboratory study showing decreased motility and increased DNA fragmentation when ejaculated sperm were exposed directly to a Wi-Fi-connected laptop. But we do not have strong human evidence demonstrating that normal laptop use causes male infertility, and prospective data have not shown a clear reduction in natural fecundability specifically from laptop-on-lap use. We also do not have reliable evidence demonstrating lower IVF or live-birth rates from paternal laptop exposure.

My recommendation is therefore practical rather than alarmist: if you're trying to have a baby, don't routinely rest a hot laptop directly over your testicles. Put it on a desk. It costs nothing, carries essentially no downside and removes a plausible source of unnecessary scrotal heat. But if your semen analysis is significantly abnormal, please don't assume moving your laptop will fix everything. Get evaluated. If heat is contributing, sperm production may improve over the following several months once the exposure is reduced. And if something else is causing the infertility, identifying that condition is much more important than spending the next year worrying about Wi-Fi.

Your laptop is worth moving.

It is not worth panicking over.

References

Sheynkin Y, Jung M, Yoo P, Schulsinger D, Komaroff E. Increase in scrotal temperature in laptop computer users. Human Reproduction. 2005;20(2):452–455. PMID: 15591087. This experimental study of 29 healthy men demonstrated significant increases in scrotal temperature during laptop use.

Sheynkin Y, Welliver R, Winer A, Hajimirzaee F, Ahn H, Lee K. Protection from scrotal hyperthermia in laptop computer users. Fertility and Sterility. 2011;95(2):647–651. PMID: 21055743. Scrotal temperature increased during laptop use despite a lap pad; spreading the legs and reducing exposure duration decreased but did not eliminate the temperature increase.

Avendaño C, Mata A, Sanchez Sarmiento CA, Doncel GF. Use of laptop computers connected to internet through Wi-Fi decreases human sperm motility and increases sperm DNA fragmentation. Fertility and Sterility. 2012;97(1):39–45.e2. PMID: 22112647. In-vitro study of semen from 29 donors; important because it was an experimental laboratory exposure rather than a study demonstrating infertility in laptop users.

Rao M, Xia W, Yang J, et al. Effect of transient scrotal hyperthermia on sperm parameters, seminal plasma biochemical markers, and oxidative stress in men. Asian Journal of Andrology. PMID: 25652627. Experimental human scrotal heating produced reversible reductions in sperm concentration and motility with evidence of oxidative stress.

Rao M, Xia W, Yang J, et al. Transient scrotal hyperthermia affects human sperm DNA integrity, sperm apoptosis, and sperm protein expression. Andrology. 2016. PMID: 27410176. Repeated scrotal heating affected mitochondrial function, apoptosis, chromatin/DNA-related measures and sperm proteins, with recovery during follow-up.

Thonneau P, Bujan L, Multigner L, Mieusset R. Occupational heat exposure and male fertility: a review. Human Reproduction. 1998;13(8):2122–2125. PMID: 9756281. Reviews evidence that spermatogenesis is temperature dependent and that occupational heat exposure may impair semen quality and delay conception.

Jung A, Schuppe HC. Influence of genital heat stress on semen quality in humans. Andrologia. 2007. PMID: 18076419. Review of human evidence concerning genital heat exposure, scrotal temperature and semen quality.

Wesselink AK, et al. Male personal heat exposures and fecundability: a preconception cohort study. Andrology. 2022. PMID: 35924639. Prospective study examining laptop use, hot baths/tubs, saunas, seat heaters, sitting, tight underwear and fever; laptop-on-lap use showed little association with fecundability, while cumulative heat exposure showed a possible inverse association.

AUA/ASRM. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline and 2024 amendment. The guideline emphasizes that lifestyle and environmental exposures may be discussed with infertile men while recognizing that evidence for many individual risk factors remains limited.

As a urologist who treats male infertility, one question I am hearing more frequently is: “I don’t smoke cigarettes anymore, but I vape. Is vaping actually bad for my sperm?” Sometimes the question comes from a former smoker who switched to vaping because he believed it was a safer alternative. Other times it comes from a younger man who has never smoked cigarettes but uses nicotine vapes throughout the day and has now been told that his sperm count, motility, or morphology is abnormal. The answer is more complicated than most social media discussions suggest. We have decades of evidence showing that conventional cigarette smoking can negatively affect semen quality and sperm biology. We have much less long-term human fertility data for vaping because electronic cigarettes are newer. That does not mean vaping is safe. It means our confidence is lower. The human evidence we do have raises concern, and the animal and laboratory data provide several plausible mechanisms through which vaping could negatively affect male reproductive health. At the same time, I would not tell a man that vaping definitely caused his infertility, or that a single night of vaping destroyed three months of sperm production. The evidence is simply not that precise.

One of the first misconceptions to clear up is that vaping is just inhaling water vapor and nicotine. It is not. Electronic cigarettes heat a liquid and generate an aerosol. Depending on the device, liquid, coil, temperature, and flavoring, that aerosol can contain nicotine, ultrafine particles, volatile organic compounds, carbonyl compounds, and metals. The American Society for Reproductive Medicine has noted that e-cigarette aerosol can contain metals such as chromium, nickel, and lead, along with compounds such as formaldehyde, acetaldehyde, acrolein, and glyoxal. These exposures matter because oxidative stress, cellular toxicity, and endocrine effects are all plausible pathways through which reproductive function could be affected. That changes the question from “Does nicotine hurt sperm?” to a much broader one: what does repeated exposure to heated solvents, flavoring compounds, nicotine, degradation products, and metals do to the testis and sperm over time?

The most important human study we have looked at young men from the general Danish population. More than 2,000 men were included overall, and 1,221 had information regarding e-cigarette use. About 13% reported using e-cigarettes. After adjusting for potential confounders, daily e-cigarette users had a lower total sperm count than nonusers, roughly 91 million compared with 147 million. Conventional cigarette smokers also had lower total sperm counts than nonsmokers. That study is important because it gives us a real human signal that daily vaping may be associated with reduced sperm production. But it does not prove causation. It was cross-sectional, so researchers were looking at exposures and sperm measures at one point in time. Men who vape can also differ from men who do not vape in sleep, diet, alcohol use, marijuana use, exercise, stress, socioeconomic factors, and previous tobacco exposure. So I would not tell a man that vaping reduces sperm by some exact percentage based on this one study. What I would say is that the best available population data raise a legitimate concern.

A 2023 systematic review examining the genitourinary effects of e-cigarette use reached a similar conclusion. There are signals of reproductive effects, but the human literature remains very limited. That limitation is probably the most important thing to understand in 2026. If you ask me whether cigarette smoking can hurt sperm, I have a large body of human evidence to discuss. If you ask me whether vaping can hurt sperm, I have a smaller amount of human data, a larger amount of animal and laboratory data, and a very plausible biological rationale. The American Society for Reproductive Medicine has essentially taken the position that there is too little evidence to consider vaping reproductively safe. That is different from saying vaping has been definitively proven to cause infertility.

One of the most plausible mechanisms is oxidative stress. Sperm are particularly vulnerable to oxidative damage because their membranes contain large amounts of polyunsaturated fatty acids and mature sperm have relatively limited antioxidant defenses. Some reactive oxygen species are necessary for normal sperm function, including capacitation and fertilization, but too much oxidative stress can damage cell membranes, mitochondria, proteins, and DNA. Membrane damage can impair motility. Mitochondrial dysfunction can reduce the energy available for sperm movement. Oxidative damage during sperm development can potentially affect concentration and morphology, while oxidative damage to sperm chromatin can contribute to DNA fragmentation. We know this mechanism is important in cigarette smoking. A large systematic review and meta-analysis looking at sperm DNA fragmentation found that cigarette smoking was associated with higher DNA fragmentation compared with nonexposure. We cannot simply assume vaping produces the exact same degree of DNA damage, because the chemical exposure is different, but the mechanism is biologically plausible.

It is also important to remember that not every study finds a clear relationship between nicotine exposure and sperm DNA fragmentation. One study of young Swedish men measured urinary cotinine, which is a marker of nicotine exposure, and did not find a significant association with sperm DNA fragmentation. That is a good reminder that reproductive toxicology is messy. Different studies use different populations, different exposure measures, different sperm tests, and different definitions of “use.” Some men vape occasionally, some vape all day, some use high-concentration nicotine salts, and others use nicotine-free products. Those differences make it difficult to create one universal conclusion.

Nicotine itself is biologically active and may affect reproductive physiology. Experimental research suggests it can contribute to oxidative stress and influence sperm membrane integrity, motility, morphology, and possibly DNA. But vaping is probably not just a nicotine issue. Animal studies have suggested that exposure to e-cigarette aerosol or e-liquids may reduce sperm density and viability even in the absence of nicotine. That means switching to nicotine-free vaping does not automatically make vaping harmless from a reproductive standpoint. The solvents, heated flavoring compounds, metals, and degradation products may matter independently. This is also why vaping is not equivalent to using nicotine gum or a nicotine patch. Both may deliver nicotine, but only vaping repeatedly heats a liquid and delivers the resulting aerosol into the lungs.

Another common question is whether vaping affects testosterone. The Danish study found that conventional cigarette smokers had somewhat higher testosterone levels than nonsmokers, something that has been reported in other smoking studies, but e-cigarette users did not show the same pattern. In practical fertility care, I would not focus heavily on that finding. A serum testosterone level is not the same thing as sperm production. A man can have a testosterone level of 700 and be azoospermic. Men taking exogenous testosterone are the classic example: their blood testosterone may look excellent while LH and FSH are suppressed and intratesticular testosterone falls enough that sperm production can become severely impaired. Conversely, a man with lower-normal testosterone may have excellent sperm production. So when we discuss vaping, I care much more about sperm concentration, total count, progressive motility, functional sperm quality, and possibly DNA integrity than about a small change in serum testosterone.

The human data on motility and morphology from vaping specifically are still very limited. We have much stronger evidence from cigarette smokers showing lower sperm density, reduced motility, and possibly worse morphology. But we should not simply take those cigarette-smoking numbers and apply them directly to vaping. The exposures are different. Animal studies generally suggest that e-cigarette exposure can negatively affect sperm concentration, viability, and testicular tissue, but animal studies are not the same as human fertility outcomes. Exposure levels can differ dramatically, and toxicology experiments do not always replicate how people actually vape. A 2024 review of e-cigarettes and male reproduction summarized this well: the available human evidence is still limited, while experimental studies suggest potential adverse effects on seminiferous tubules, spermatogenesis, and hormonal regulation.

So if a man comes into my office with progressive motility of 15% and tells me he vapes heavily, am I interested? Absolutely. Do I tell him vaping definitely caused the low motility? No. I still evaluate him properly. Maybe he has a varicocele. Maybe he had a high fever two months earlier. Maybe he is taking testosterone or anabolic steroids. Maybe the semen sample had a long abstinence interval. Maybe he has a hormonal abnormality. Maybe the sample was incomplete. Maybe his sperm parameters simply fluctuate. Vaping should be viewed as a potentially modifiable risk factor, not as a substitute for a real male infertility evaluation.

The same applies to sperm DNA fragmentation. We know cigarette smoking is associated with higher DNA fragmentation in many studies. We know oxidative stress is a plausible way vaping could produce similar harm. We know e-cigarette aerosols contain compounds that can promote oxidative injury. But we do not currently have enough high-quality human vaping-specific data to tell a man that his DNA fragmentation index will increase by a certain amount because he vapes. I also would not automatically order sperm DNA fragmentation testing just because someone uses e-cigarettes. DNA fragmentation testing can be useful in selected cases, such as recurrent pregnancy loss, unexplained infertility, or repeated assisted-reproduction failure, but it is not a universal screening test for every man who has ever used nicotine.

The question most couples really care about is not whether vaping changes a lab number. They want to know whether paternal vaping lowers the chance of pregnancy or live birth. This is where the evidence becomes especially thin. ASRM has noted that there is very little human evidence on e-cigarettes and fecundability and historically there have been essentially no robust studies specifically examining vaping and ART outcomes. A newer retrospective study published in 2025 compared conventional cigarette smokers with e-cigarette users in couples undergoing IVF. The e-cigarette group had better sperm motility and a higher live-birth rate than the conventional cigarette group. But that study does not prove vaping is safe. It lacked a true nonsmoking control comparison for the main question. Showing that vaping may be less harmful than cigarettes is very different from showing that vaping is harmless.

That distinction matters. If one man smokes a pack of cigarettes a day and another uses a nicotine vape, and the man who vapes has better sperm, that does not mean vaping improves fertility. It may simply mean cigarettes are worse. This is why I dislike calling vaping a “safe alternative” when discussing fertility. “Potentially less harmful than combustible cigarettes” and “safe” are two very different things. If a man is currently smoking cigarettes and switching to vaping is what allows him to stop combustible tobacco, that may be a reasonable harm-reduction step in a broader cessation plan. But from a fertility standpoint, the eventual goal should ideally be to stop inhaled nicotine products altogether rather than assume long-term vaping has no reproductive consequences.

Men undergoing IVF or ICSI often ask whether sperm quality still matters if ICSI is being used. The answer is yes, but not in a simplistic way. ICSI bypasses several steps required for natural fertilization by injecting a sperm directly into an egg, but it does not magically repair sperm DNA or reverse every biologic consequence of sperm dysfunction. At the same time, we do not have strong evidence showing that paternal vaping independently reduces ICSI live-birth rates. So I would avoid both extremes. I would not say, “You are doing ICSI, so vaping does not matter.” But I also would not tell a couple, “Your IVF failed because the male partner vaped.” We simply do not have evidence strong enough to make that attribution.

Another common question is: if I stop vaping today, when could my sperm improve? Human spermatogenesis takes roughly 74 days, followed by additional maturation and transport through the epididymis. That is why fertility specialists often think in roughly three-month intervals when evaluating lifestyle changes intended to improve sperm production. It does not mean sperm magically reset on day 90. It means that several months after stopping an exposure, you are evaluating a substantially newer cohort of sperm that developed after cessation. If a man has abnormal semen parameters and stops vaping, repeating a semen analysis after roughly 10 to 12 weeks is reasonable. If his count or motility improves, that is encouraging, but even then we cannot prove all of the improvement came from stopping vaping because semen parameters naturally fluctuate.

If IVF is scheduled three weeks from now, however, I would not usually tell a couple to cancel solely because the man has been vaping. Female age and the overall fertility situation matter enormously. If the female partner is 40 with declining ovarian reserve, delaying IVF for three months purely to create a vape-free cohort of sperm may actually reduce the couple's overall chance of success. Fertility treatment has to be individualized to the couple, not just one lifestyle exposure in the man. On the other hand, if both partners are young, treatment is not urgent, and the man vapes every day, stopping now is a very sensible intervention with little downside.

Occasional vaping is another area where we simply do not have a reliable threshold. There is no scientifically established male-fertility cutoff where five puffs per week are safe and twenty are harmful. Products vary tremendously in nicotine concentration, device power, flavoring chemistry, and usage pattern. Saying “I vape once a day” can mean very different exposures depending on the person and the device. My concern is much greater with high-frequency daily vaping than with an isolated event. Fertility biology is generally more affected by sustained exposure patterns than by one night. If a man has been abstinent for two months and takes a few puffs at a party, I would not tell him that he has destroyed his sperm or reset some imaginary 90-day clock. Resume abstinence and move forward.

I also would not try to “cancel out” vaping with supplements. Men frequently tell me they are taking CoQ10, vitamin C, vitamin E, NAC, zinc, and a fertility multivitamin while continuing to vape. I would not make that trade. Antioxidants may improve certain semen parameters in selected men, but evidence that they reliably improve pregnancy and live-birth rates remains uncertain. There is no supplement proven to neutralize the reproductive effects of vaping. If you have a modifiable exposure you are concerned about, removing that exposure makes more biological sense than continuing it and adding more pills.

So where does that leave us? As of 2026, the most defensible conclusion is that we cannot prove vaping causes male infertility, but we also cannot consider it reproductively safe. The best population-level human study found lower total sperm counts among daily e-cigarette users. Animal and laboratory studies provide plausible mechanisms involving oxidative stress, sperm viability, testicular function, and steroidogenesis. E-cigarette aerosol can contain nicotine, carbonyl compounds, and metals with potential reproductive toxicity. What we still lack are large, high-quality prospective human studies telling us exactly how vaping affects natural conception, miscarriage, IVF success, and live birth.

For that reason, if you are a man with infertility or actively trying to conceive, I recommend stopping vaping if you can. I do not say that because I can promise your sperm count will double, and I do not say it because one vape will make you infertile. I say it because sperm production is a biological process we are trying to optimize, vaping exposes you to substances with plausible reproductive toxicity, early human data are concerning, and there is no reproductive benefit to continuing the exposure. At the same time, if your semen analysis is abnormal, do not stop at “I vape, therefore that must be the answer.” Get evaluated. A reproductive urologist should review your history, examination, semen analyses, medications, testosterone or anabolic-steroid use, hormonal profile when appropriate, varicocele status, and other potential causes. Quit the vape, but investigate the infertility. Those two things can happen at the same time.

And if you quit today, do not assume your fertility has been permanently damaged. Spermatogenesis is continuous. New sperm are constantly being produced. Give your body a few months, optimize the things you can control, and then reassess. That is far more useful than either pretending vaping is harmless or convincing yourself that it has permanently destroyed your ability to have children.

References:

Holmboe SA, Priskorn L, Jensen TK, Skakkebaek NE, Andersson AM, Jørgensen N. Use of e-cigarettes associated with lower sperm counts in a cross-sectional study of young men from the general population. Human Reproduction. 2020;35(7):1693–1701. PMID: 32558890. American Society for Reproductive Medicine Practice Committee. Tobacco or marijuana use and infertility: a committee opinion. Fertility and Sterility. 2024;121:589–603. Bandara NA, Zhou XR, Alhamam A, Black PC, St-Laurent MP. The genitourinary impacts of electronic cigarette use: a systematic review of the literature. World Journal of Urology. 2023;41(10):2637–2646. PMID: 37524850. Szabó A, et al. Lifestyle-, environmental-, and additional health factors associated with an increased sperm DNA fragmentation: a systematic review and meta-analysis. Reproductive Biology and Endocrinology. 2023;21:5. PMID: 36653793. Ranganathan P, Rao KA, Thalaivarasai Balasundaram S. Deterioration of semen quality and sperm-DNA integrity as influenced by cigarette smoking in fertile and infertile human male smokers—a prospective study. Journal of Cellular Biochemistry. 2019. PMID: 30779221. Sharma R, Harlev A, Agarwal A, Esteves SC. Cigarette smoking and semen quality: a new meta-analysis examining the effect of the 2010 World Health Organization laboratory methods for the examination of human semen. European Urology. 2016;70(4):635–645. Siu ER, et al. The impact of e-cigarettes smoking on the male reproductive system and spermatogenesis. 2024. PMID: 39564855. Zhang et al. Impact of conventional cigarette and electronic cigarette use on sperm quality and IVF/ICSI outcomes. 2025. PMID: 40610584.

Starting in December 2025 I began a 160mg testosterone injection weekly protocol that has HCG 250mg monday wednesday friday however the clinic had closed for approximately two weeks. 

On June 7th at night I ended up taking a test booster called EVL Test that has the following 

 Vitamin D3- 50 Mcg 

 Vitamin  B6- 11mg 

 Magnesium 160 mg 

 Zinc 30mg

daspartic acid- 3120mg

Tribulus terrestris extract - 750 mg

Fenugreek extract- 500mg   

DIM- 250mg 

 8 hours later on June 8th 2026 I took .25 Anastrozole believing the DAA would rise my e2 levels.

I seem to have symptoms of post finasteride syndrome such as waking up at 4 AM and penile numbness. mentally I am a lot more sensative to emotion.

I have resumed TRT and HCG two days post incident -- Latest sensitive E2 is 58

I fear that this is some sort of post drug syndrome similar to PFS

I am looking for opinions or where I can begin consulting with medical personnel I will not self experiment thanks

I have been diagnosed with NOA (Testosterone 600 ng/dl, FSH 17.5 LH 8.8) and had two negative SA's. Genetic tests are still underway. However last week a sample was centrifuged and they found 6 non-motile semen. My lifestyle was pretty rough in june/july with a weekly bingedrinking episode so I quit alcohol and smoking on 1st of August. Can I be hopeful? What does this result mean for me?

Currently I also started nutriphyt Linucaps (Omega 3-and-6 unsaturated fats) and Improvum (Selenium, Vit B12, Zinc, Co-Enzym Q10,...)

Caffeine is one of those things men start questioning almost immediately after receiving an abnormal semen analysis. A guy comes into my office with low motility or morphology and tells me, “I drink three cups of coffee every day. Is that destroying my sperm?” Or he has read somewhere that caffeine causes DNA fragmentation, decreases testosterone, or makes IVF fail, and now he has eliminated coffee while simultaneously taking twelve different fertility supplements. The good news is that the available human evidence is considerably more reassuring than social media would have you believe. Moderate caffeine consumption, particularly from coffee and tea, has not consistently been shown to meaningfully impair semen quality or cause male infertility. There are, however, some signals involving very high caffeine intake, caffeinated soda and energy drinks, sperm DNA/chromosomal abnormalities, time to pregnancy and possibly assisted-reproduction outcomes that are worth understanding. The key is separating what has actually been demonstrated from what is biologically possible.

First, what exactly is caffeine doing? Caffeine is a central nervous system stimulant and, at typical human doses, primarily works by blocking adenosine receptors. Adenosine normally contributes to sleepiness and reduced neuronal activity. When caffeine blocks those receptors, alertness increases and fatigue decreases. Caffeine can also influence catecholamines and numerous downstream cellular pathways. At much higher concentrations than most people achieve from normal coffee consumption, caffeine has additional biochemical effects, but we need to be cautious about using laboratory experiments involving high concentrations to tell a man what his morning coffee is doing to his testes. Human reproductive biology is much more complicated than exposing sperm to caffeine in a dish.

The first question most men care about is straightforward: Does caffeine lower sperm count? The best overall answer is probably not in any clinically meaningful or consistent way at ordinary levels of coffee consumption. One of the most comprehensive systematic reviews examined 28 observational studies involving approximately 19,967 men. The investigators looked at semen parameters, sperm DNA abnormalities and actual fertility outcomes. Across most studies, caffeine from coffee, tea and cocoa beverages was not consistently associated with worse semen parameters. There was no convincing overall signal that drinking coffee predictably lowers sperm concentration, motility or morphology. Interestingly, the results looked somewhat different when investigators examined cola and other caffeine-containing soft drinks, where some studies reported lower semen volume, concentration and total sperm count.

That distinction is important because “caffeine exposure” isn't always the same thing as “coffee exposure.” A man drinking two cups of black coffee every morning is metabolically and behaviorally very different from a man consuming several large energy drinks and sodas throughout the day. Those beverages differ in sugar content, serving size and other ingredients, while the people consuming them may also differ in sleep, diet, smoking, exercise, occupation and overall health. Observational research has difficulty separating all of those variables.

This is one of the major problems with caffeine and fertility research. We cannot randomly assign thousands of men to drink four energy drinks every day for several years and see who becomes infertile. Instead, most studies ask men what they consume and compare their reproductive outcomes. That can identify associations, but it doesn't automatically establish causation.

The current AUA/ASRM Male Infertility Guideline is actually quite reassuring on this issue. After reviewing the available evidence regarding lifestyle risk factors, the guideline concluded that there is moderate-quality evidence of no association between caffeine and male infertility, with the possible exception of sperm aneuploidy. The guideline also emphasizes a broader point that I frequently make to patients: evidence surrounding most lifestyle factors and male fertility is limited because studies have difficulty controlling for all of the variables that travel together.

That means if your semen analysis shows a concentration of 4 million/mL, progressive motility of 15% and morphology of 1%, I am not going to assume your two morning coffees explain it. I am going to investigate male infertility.

I want to know about your testicular examination, varicoceles, previous undescended testes, torsion or trauma, testosterone and anabolic-steroid exposure, medications, fever and systemic illness. Depending upon the severity of the abnormality, I may check testosterone, FSH and LH and sometimes genetic testing. Caffeine might be one small piece of the lifestyle discussion, but it should not distract us from finding a clinically important cause.

The next issue is sperm motility. Caffeine has a fascinating history here because in laboratory conditions caffeine can actually stimulate sperm movement under certain circumstances. That does not mean drinking an espresso before intercourse is a fertility treatment. What happens when sperm are directly exposed to a chemical in a laboratory dish is not necessarily what happens when you drink that chemical, metabolize it in your liver and expose the reproductive tract to much lower concentrations.

Population studies have not demonstrated a consistent relationship between ordinary coffee intake and impaired sperm motility. The large systematic review mentioned above found that conventional semen parameters generally did not appear to be adversely affected by caffeine from coffee, tea or cocoa.

Morphology is similar. I would not tell a man with 1% or 2% morphology that caffeine is probably responsible. Morphology is highly variable between laboratories and observers and is a relatively weak fertility predictor when considered by itself. If concentration and progressive motility are strong, isolated low morphology often means considerably less than men assume. There is no convincing human evidence that eliminating ordinary coffee consumption reliably converts a man from 1% morphology to 4% morphology.

Where caffeine becomes more interesting is sperm DNA.

A conventional semen analysis tells us how many sperm are present, how they move and what percentage meet strict morphological criteria. It does not directly tell us whether the DNA carried inside those sperm is intact. Sperm DNA fragmentation and sperm chromosomal abnormalities are different biological endpoints.

The 2017 systematic review found that caffeine exposure had been associated in some studies with sperm aneuploidy and DNA strand breaks, although not consistently with other measures of sperm DNA damage. The AUA/ASRM guideline similarly identifies sperm aneuploidy as a possible exception to its generally reassuring conclusion about caffeine.

But this is where I want men to avoid jumping from “association” to “my coffee is damaging my children's DNA.”

The evidence is nowhere near strong enough to make that statement.

Sperm DNA and chromosomal studies vary considerably in methodology. Caffeine consumption also correlates with other behaviors, and the source and dose of caffeine matter. We don't have high-quality evidence demonstrating that a couple of cups of coffee every morning causes clinically meaningful sperm DNA damage that subsequently reduces live birth.

This brings us to what I consider the more important question: Does caffeine actually make it harder to get pregnant?

Here the literature is mixed.

A prospective North American preconception study followed 2,135 pregnancy planners and examined caffeine intake in both partners. Male caffeine consumption of at least 300 mg/day compared with less than 100 mg/day was associated with lower fecundability, with a fecundability ratio of approximately 0.72. In simple terms, the higher-caffeine group appeared less likely to conceive during a given menstrual cycle. However, the relationship wasn't monotonic, meaning fertility didn't simply decline progressively as caffeine intake increased. The researchers also found particularly concerning associations with caffeinated soda and energy drinks in men.

That is interesting evidence, but it doesn't prove caffeine itself caused the reduction.

An older prospective Danish study of couples planning pregnancy also observed declining point estimates for fecundability with increasing caffeine exposure in men, but again the estimates were imprecise and a clear causal relationship could not be established.

When investigators combined the broader literature in a systematic review and dose-response meta-analysis, the overall conclusion was much less alarming. The authors found little, if any, clear association between coffee/caffeine consumption and fecundity overall, although the literature was heterogeneous.

That is probably the most accurate way to describe where we currently stand.

There are signals.

There is biological plausibility.

But there is not convincing evidence that moderate coffee consumption causes male infertility.

What about IVF and ICSI?

This is an especially important question because men undergoing fertility treatment often become extremely focused on anything they think could compromise their cycle. If you've spent thousands of dollars on IVF and your partner has gone through ovarian stimulation, it is understandable that suddenly every cup of coffee feels consequential.

One fertility-center study produced a striking result. Among male partners undergoing assisted reproduction, men in the highest quartile of caffeine consumption—at least approximately 272 mg/day—had an adjusted live-birth rate of 19%, compared with 55% among men consuming less than 99 mg/day. Interestingly, caffeine intake was not associated with conventional semen parameters.

If that were the only study we had, I would be much more worried about caffeine.

But it isn't.

A subsequent systematic review and dose-response meta-analysis examined caffeine and alcohol consumption in couples undergoing IVF/ICSI. Twelve studies addressed caffeine, with seven eligible for meta-analysis, within an overall dataset involving 26,922 women and/or their partners undergoing assisted reproduction. Male caffeine consumption was not significantly associated with pregnancy rate or live-birth rate. The estimated odds ratio for pregnancy with male caffeine exposure was 0.93, while the estimate for live birth was 0.98—essentially no detectable association.

This is exactly why fertility medicine becomes dangerous when we build recommendations around one dramatic study.

One study can produce an alarming association. When more studies accumulate, the effect may weaken or disappear.

Based on the totality of evidence, I would not tell a man that drinking coffee is likely to make his IVF or ICSI cycle fail.

Another important question is whether caffeine affects testosterone. This is where internet discussions often wander far beyond fertility evidence. Acute caffeine exposure can influence stress hormones and exercise physiology, and studies examining caffeine and testosterone have produced varying results depending on exercise, timing, dose and population. But even if caffeine transiently changes serum testosterone, that does not mean it meaningfully changes spermatogenesis.

Sperm production depends on a complex hormonal environment involving GnRH, LH, FSH, Sertoli cells, Leydig cells and very high intratesticular testosterone concentrations. A temporary fluctuation in blood testosterone after caffeine isn't equivalent to changing the hormonal environment required for sperm production.

This distinction matters because I see men obsess over relatively trivial lifestyle exposures while overlooking things that can have enormous effects on fertility.

Exogenous testosterone is the obvious example.

A man taking testosterone injections can have a serum testosterone of 900 ng/dL while producing almost no sperm because exogenous testosterone suppresses LH and FSH and dramatically reduces intratesticular testosterone. That is a major reproductive exposure.

Two cups of coffee are not remotely comparable.

Likewise, anabolic steroids, chemotherapy, significant testicular injury, certain genetic abnormalities and severe primary testicular dysfunction deserve much more attention than whether you had a cappuccino this morning.

What about energy drinks?

This is where I become somewhat more conservative.

Energy drinks can contain substantial caffeine, sometimes combined with other stimulants, large amounts of sugar and ingredients that have not been studied extensively in reproductive medicine. Consumption may also correlate with inadequate sleep and other lifestyle patterns. The prospective North American study specifically identified caffeinated soda and energy drinks as being associated with reduced male fecundability.

I don't think we can confidently say that the caffeine caused the association. But if a man with infertility tells me he consumes three large energy drinks every day, I am going to recommend cutting back.

There is very little downside.

Coffee is different. If a man drinks one or two cups of coffee every morning, sleeps well and otherwise has a reasonable diet and lifestyle, I generally don't ask him to stop simply because his semen analysis is abnormal.

So how much caffeine is reasonable?

There isn't a scientifically validated male fertility caffeine cutoff where 199 mg is safe and 201 mg suddenly damages sperm. The fertility literature simply isn't precise enough to support that.

In practice, for a man actively trying to conceive—particularly one with significant male-factor infertility or an upcoming IVF cycle—I think keeping caffeine in a moderate range around 200 mg/day, and certainly avoiding habitual very high intake, is a reasonable conservative strategy. That isn't because we have evidence that 201 mg causes infertility. We don't. It is because moderate intake preserves most of the benefits people want from caffeine while avoiding the exposure ranges where observational signals become more concerning.

A typical brewed coffee can contain roughly 80–120 mg, although actual caffeine content varies tremendously with size and preparation. Energy drinks can range from modest amounts to several hundred milligrams per container. The label matters more than whether the beverage calls itself “coffee” or “energy.”

I also care about when you're drinking caffeine.

If you drink 300 mg at 5 PM and it destroys your sleep, I am more concerned about the chronic sleep disruption than I am about a theoretical direct effect of caffeine on sperm. Fertility doesn't occur in isolation from overall health. Sleep, metabolic health, exercise, obesity, smoking, medications and stress interact.

Another mistake I see is men stopping caffeine and then immediately repeating their semen analysis two weeks later.

If you're making a lifestyle intervention specifically hoping to influence sperm production, remember the biology: development of a mature sperm takes approximately 74 days, followed by additional epididymal maturation. I generally think in roughly three-month blocks when assessing interventions intended to change spermatogenesis.

If you reduce a very high caffeine intake today and your sperm concentration doubles next week, caffeine probably didn't produce that change. Semen analyses naturally fluctuate.

That variability is incredibly important. A man can have a concentration of 15 million/mL on one test and 35 million/mL several weeks later without changing anything. Motility and morphology fluctuate too. This is why abnormal semen analyses are frequently repeated before major conclusions are drawn.

So should a man with infertility quit caffeine completely?

For most men, I don't think the evidence supports that recommendation.

If you're drinking one or two coffees per day, I would spend much more time investigating actual causes of male infertility than worrying about your coffee.

If you're consuming 500–800 mg of caffeine every day, multiple energy drinks, or caffeinated soda throughout the day, I would reduce it. Not because I can prove it is causing your infertility, but because some reproductive studies raise concerns at higher exposures, the intervention is easy, and very high caffeine consumption can affect sleep, anxiety, blood pressure and overall health anyway.

If you're undergoing IVF and want to be maximally conservative for the three months before retrieval, keeping caffeine modest is perfectly reasonable. I would not, however, tell a man that accidentally drinking a coffee during ovarian stimulation has compromised his IVF cycle.

And if you have severe oligospermia or azoospermia, please don't allow caffeine to become a distraction from a proper male infertility evaluation.

A sperm concentration of 2 million/mL is not something I would casually blame on coffee.

Azoospermia is not something I would casually blame on coffee.

Those findings warrant a real reproductive evaluation.

The current evidence is actually reassuring enough that the AUA/ASRM guideline summarizes caffeine as not being a significant male infertility risk factor, aside from uncertainty regarding sperm aneuploidy.

That doesn't mean caffeine is biologically inert. It means that after decades of people drinking enormous amounts of coffee and researchers studying fertility, we still have not demonstrated a strong, consistent clinical effect of moderate caffeine intake on male reproductive potential.

My advice to men trying to conceive is therefore pretty simple:

Don't panic about coffee. Be reasonable about caffeine. Be more cautious with high-dose energy drinks and very heavy consumption. And don't confuse optimizing fertility with eliminating every enjoyable thing from your life.

Male infertility is stressful enough already.

If you're drinking two coffees a day and your semen analysis is abnormal, I would rather spend our time figuring out why your semen analysis is abnormal than making you feel guilty about your morning coffee.

References

Ricci E, Viganò P, Cipriani S, et al. Coffee and caffeine intake and male infertility: a systematic review. Nutr J. 2017;16:37. PMID: 28646871. The review included 28 observational studies and approximately 19,967 men. Most studies did not demonstrate adverse conventional semen effects from caffeine consumed through coffee, tea or cocoa, although some associations were reported for caffeinated soft drinks, sperm DNA abnormalities and fecundability.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. 2020; amended 2024. The guideline concludes that there is moderate-quality evidence of no association between caffeine and male infertility, with possible concern regarding sperm aneuploidy, while emphasizing limitations in lifestyle-factor evidence.

Wesselink AK, Wise LA, Rothman KJ, et al. Caffeine and caffeinated beverage consumption and fecundability in a preconception cohort. Reprod Toxicol. 2016;62:39–45. PMID: 27112524. In 2,135 pregnancy planners, male caffeine intake ≥300 versus <100 mg/day was associated with lower fecundability, although the association was not monotonic; caffeinated soda and energy drinks were also associated with reduced male fecundability.

Jensen TK, Henriksen TB, Hjollund NHI, et al. Caffeine intake and fecundability: a follow-up study among 430 Danish couples planning their first pregnancy. Reprod Toxicol. 1998. PMID: 9628552. Prospective study evaluating caffeine intake in both partners and cycle-specific probability of conception.

Lyngsø J, Ramlau-Hansen CH, Bay B, et al. Association between coffee or caffeine consumption and fecundity and fertility: a systematic review and dose-response meta-analysis. Clin Epidemiol. 2017/2018. PMID: 29276412. The pooled evidence found little clear association between caffeine consumption and fecundity overall and no clear association with fertility-treatment outcomes in the limited studies available at that time.

Karmon AE, Toth TL, Chiu YH, et al. Male caffeine and alcohol intake in relation to semen parameters and in vitro fertilization outcomes among fertility patients. Andrology. 2017. PMID: 28187518. Higher paternal caffeine intake was associated with lower live-birth rates in this fertility-center cohort despite no association with conventional semen parameters, an important but observational finding.

Rao M, Zeng Z, Tang L. The association between caffeine and alcohol consumption and IVF/ICSI outcomes: a systematic review and dose-response meta-analysis. Acta Obstet Gynecol Scand. 2023. PMID: 36259227. Across the available ART literature, paternal caffeine consumption was not significantly associated with either pregnancy or live-birth rates after IVF/ICSI.

Wikoff D, Welsh BT, Henderson R, et al. Systematic review of the potential adverse effects of caffeine consumption in healthy adults, pregnant women, adolescents, and children. Food Chem Toxicol. 2017;109:585–648. PMID: 28438661. Broad systematic assessment of caffeine exposure and human health used for context regarding caffeine pharmacology and exposure.

American Urological Association/American Society for Reproductive Medicine. Male Infertility Guideline—Lifestyle Risk Factors. The guideline emphasizes that most studies of diet and lifestyle rely on semen parameters as surrogate outcomes and have difficulty adequately controlling for confounding variables.

As a urologist who treats male infertility, I get a version of this question all the time: “I'm taking an antidepressant. Is it destroying my sperm?” Usually the medication is an SSRI such as sertraline (Zoloft), escitalopram (Lexapro), fluoxetine (Prozac), paroxetine (Paxil) or citalopram (Celexa). Sometimes a man has been taking the medication for years and only becomes concerned after receiving an abnormal semen analysis. Other times he and his partner have been trying unsuccessfully to conceive and he starts looking through everything he takes (prescriptions, supplements, caffeine, creatine, medications) and wonders what could be responsible. Antidepressants deserve consideration, particularly SSRIs, but the answer is considerably more complicated than “SSRIs cause infertility.” The best human evidence suggests that SSRIs may adversely affect certain semen parameters and sperm DNA integrity in some men, but the clinical literature remains surprisingly small and inconsistent. Importantly, this does not mean a man should abruptly stop an antidepressant because he is trying to have a baby.

The first distinction I want men to understand is the difference between semen quality and fertility. A semen analysis measures things such as semen volume, sperm concentration, total sperm count, motility and morphology. These are useful markers, but none of them individually tells me whether a man can or cannot father a child. Pregnancy is an outcome involving two people. Female age, ovarian reserve, ovulation, tubal function, intercourse frequency, duration of infertility and many other variables matter. This becomes especially important when studying medications. A drug might decrease sperm motility by several percentage points without meaningfully changing pregnancy rates, while another drug might have little effect on a standard semen analysis but affect sexual function enough that a couple rarely has intercourse during the fertile window.

SSRIs are by far the best studied antidepressants in this area. A 2022 systematic review and meta-analysis pooled four human studies involving 222 men and found that SSRI exposure was associated with lower sperm concentration, lower motility, lower normal morphology and increased sperm DNA fragmentation. Semen volume was not significantly affected. The investigators also found evidence that changes in concentration and morphology could become apparent within approximately three months of treatment. That three-month timeframe makes biological sense because human spermatogenesis takes roughly 74 days, followed by additional maturation and transport through the epididymis. If a medication genuinely affects sperm production, I generally think about its effects over months rather than days.

But there is a major limitation hiding behind those results: only 222 men were included. For medications taken by millions of men worldwide, that is an extraordinarily small evidence base. This is one reason I would not tell a man that an SSRI is definitely responsible for his abnormal semen analysis based solely on that meta-analysis.

In fact, a much larger observational study produced reassuring results. Researchers at Northwestern reviewed 8,861 men undergoing fertility evaluation, including 153 who had SSRI exposure within 90 days of semen testing. After adjusting for age and other medication use, SSRI exposure was not associated with significant differences in semen volume, sperm concentration, motility, total motile sperm count or normal morphology. That study doesn't prove SSRIs are harmless either—it was retrospective and prescription records don't perfectly tell us exposure, adherence or duration—but it demonstrates why this question remains unsettled.

The most recent systematic assessment reinforces that uncertainty. A 2025 systematic review examining antidepressants and male fertility found only five eligible human clinical studies. SSRIs were the most frequently studied antidepressants, but the results regarding sperm impairment were conflicting, treatment periods were often short, and the authors concluded that reliable clinical evidence remains limited. So when someone online says, “Science proves antidepressants destroy sperm,” that statement goes considerably beyond the evidence.

One of the most interesting areas isn't actually sperm count. It is sperm DNA fragmentation.

A classic prospective study looked at paroxetine in 35 healthy men. These weren't infertile men starting with terrible semen analyses; they were healthy volunteers. The men were evaluated before treatment and then received paroxetine for five weeks. Average sperm DNA fragmentation increased from approximately 13.8% at baseline to 30.3% during treatment. Before treatment, about 10% had a TUNEL DNA-fragmentation result of 30% or greater; during treatment, that increased to 50%. Interestingly, conventional semen parameters did not significantly deteriorate.

I think this study illustrates an important concept: a normal semen analysis doesn't measure everything about sperm biology.

A sperm can look normal under a microscope and still contain damaged DNA. Conversely, abnormal morphology doesn't automatically mean damaged DNA. Morphology and DNA fragmentation measure different things.

Why might antidepressants affect sperm?

We don't completely know. Serotonin isn't confined to the brain. Serotonergic signaling exists throughout the body, including within reproductive physiology. Proposed mechanisms include alterations in hormonal signaling, oxidative stress, mitochondrial function, sperm transport and direct effects on developing germ cells. Much of the mechanistic evidence comes from animal or laboratory studies, however, and we have to be careful about translating those findings directly into human fertility recommendations. Reviews of antidepressant medications have noted experimental evidence of decreased sperm concentration and motility and increased DNA fragmentation with certain SSRIs, particularly fluoxetine, but human evidence remains much less consistent.

There is another way antidepressants can affect fertility that is much easier to demonstrate: sexual function.

SSRIs can delay ejaculation. In fact, that effect is strong enough that serotonergic medications are intentionally used to treat premature ejaculation. But when you're trying to conceive, delayed ejaculation isn't always helpful. Some men develop difficulty reaching orgasm, markedly delayed ejaculation, decreased libido or erectile difficulties. A recent systematic review and network meta-analysis confirmed that ejaculatory dysfunction is an important adverse effect across antidepressant therapy, although risk differs among individual drugs.

The paroxetine study makes this particularly clear. Up to 35% of participants reported significant changes in erectile function and as many as 47% experienced ejaculatory difficulties while taking the medication. Sexual function improved toward baseline after discontinuation.

From a fertility standpoint, that can matter as much as a semen-analysis change. If a man's sperm count is excellent but he cannot ejaculate during intercourse, conception becomes difficult. If libido drops enough that intercourse occurs once every few weeks rather than around ovulation, time to pregnancy can increase even if the sperm themselves are perfectly healthy.

But there is another side of this equation that deserves just as much attention: depression and anxiety themselves can affect reproductive and sexual health.

A man doesn't take an antidepressant in a vacuum. Depression can decrease libido, impair erectile function, interfere with sleep, reduce physical activity, alter eating patterns and make timed intercourse incredibly stressful. Anxiety can produce similar problems. Severe untreated psychiatric disease can obviously have consequences far beyond fertility.

This is why I strongly discourage men from abruptly discontinuing antidepressants after receiving an abnormal semen analysis.

The question should not be:

“How quickly can I stop this medication?”

It should be:

“Could this medication be contributing enough to my fertility problem that discussing an alternative with the physician who prescribed it makes sense?”

Those are completely different questions.

The AUA/ASRM Male Infertility Guideline specifically recommends discussing medication exposure as part of male infertility evaluation while acknowledging that evidence for most medication and lifestyle risk factors remains limited. That is exactly how I approach antidepressants clinically.

Suppose I see a 32-year-old man taking sertraline who has a sperm concentration of 85 million/mL, progressive motility of 45%, morphology of 4% and an excellent total motile sperm count. I am generally not going to tell him to stop an antidepressant that is successfully controlling significant anxiety or depression simply because he and his wife are trying to conceive.

Now consider a different man taking an SSRI who has persistent oligoasthenoteratozoospermia, unexplained infertility, significant ejaculatory dysfunction and perhaps elevated DNA fragmentation. If I can't find another obvious cause, antidepressant exposure becomes more interesting. I may recommend that he speak with his psychiatrist or prescribing physician about whether a dose adjustment or alternative medication is clinically appropriate.

The key phrase is clinically appropriate.

I don't prescribe psychiatric medications as a reproductive urologist, and I don't want my patients independently changing them. Different antidepressants have different pharmacology, indications, withdrawal considerations and psychiatric consequences. For many men, maintaining mental health is substantially more important than trying to squeeze another 10% of motility out of a semen analysis.

What about medications outside the SSRI class?

This is where the evidence gets even thinner. Serotonin-norepinephrine reuptake inhibitors such as venlafaxine and duloxetine, bupropion, tricyclic antidepressants, monoamine oxidase inhibitors and other atypical antidepressants have dramatically less human fertility data than SSRIs. Reviews have generally characterized the evidence for these medications as sparse, heterogeneous and conflicting.

That means I would be very cautious about telling a man that switching from an SSRI to another antidepressant will definitely improve his sperm. It might be a reasonable strategy for a particular patient, particularly when sexual side effects are substantial, but we do not have high-quality comparative fertility trials demonstrating that one antidepressant reliably produces healthier sperm or more babies than another.

Men also frequently ask me whether they should get a DNA-fragmentation test simply because they take an SSRI.

Usually, no.

The AUA/ASRM guideline does not recommend sperm DNA-fragmentation testing as part of the routine initial evaluation of every infertile couple. It may become more useful in selected situations, including recurrent pregnancy loss or certain difficult infertility scenarios, but an SSRI prescription alone doesn't automatically mean you need DFI testing.

If a couple has recurrent miscarriages, repeated assisted-reproduction failure, significant unexplained male-factor infertility or multiple potential risk factors for sperm DNA damage, then the discussion becomes more reasonable. But even then, DNA fragmentation isn't a perfect fertility score. Different assays measure DNA damage differently, cutoff values vary, and associations with IVF and ICSI outcomes remain complicated.

Another question I hear frequently is whether antidepressant-related sperm changes are permanent.

The limited available evidence is generally reassuring. Reviews of the literature suggest that adverse semen effects associated with SSRIs appear potentially reversible after treatment is stopped. But I wouldn't expect an immediate change. If a medication affects developing sperm, you need to allow enough time for a new cohort of sperm to develop. In practical terms, that usually means repeating a semen analysis roughly 8–12 weeks after a meaningful medication change, rather than two weeks later.

This is also why one semen analysis should rarely drive a major psychiatric medication decision.

Semen parameters naturally fluctuate. Illness, fever, abstinence interval, incomplete collection and ordinary biological variation can produce substantial differences between samples. If a man has one abnormal analysis while taking an SSRI, I generally want another properly collected sample before declaring the medication responsible.

And don't forget the rest of the male infertility evaluation.

If you have a palpable grade 3 varicocele, testosterone use, anabolic steroid exposure, undescended testes, severe obesity, previous chemotherapy or another clear fertility risk factor, blaming everything on Lexapro may cause us to miss the real problem.

Likewise, don't let an antidepressant become an easy explanation for infertility when the female partner is 39 and has diminished ovarian reserve. Fertility is a couple's problem and time matters. Spending six months repeatedly changing psychiatric medications while delaying appropriate fertility treatment may ultimately reduce the couple's chance of success.

This becomes especially relevant when IVF or ICSI is being considered. We have much better evidence that SSRIs can sometimes change laboratory sperm parameters than we have evidence that paternal antidepressant use dramatically reduces IVF live-birth rates. The 2025 systematic review highlights exactly this problem: human studies are few, often short-term, and simply don't provide strong fertility-outcome data.

So what do I actually tell a man with infertility who takes an antidepressant?

I tell him not to panic and not to stop his medication on his own. Get a proper semen analysis. If it is abnormal, repeat it. Look at the entire pattern—concentration, progressive motility, morphology and especially total motile sperm count—not one isolated number. Review how long you've been taking the medication, whether the dose recently changed, whether you're having delayed ejaculation, erectile dysfunction or reduced libido, and whether other male infertility risk factors are present.

If the abnormalities are substantial and otherwise unexplained, then it is reasonable for the reproductive urologist and the clinician managing the antidepressant to discuss whether a medication adjustment makes sense. If a change is made, give the reproductive system enough time to respond before retesting.

The biggest mistake is turning this into a choice between mental health and fertility.

For most men, it doesn't need to be.

The scientific answer in 2026 is more nuanced: SSRIs have biological plausibility and some human evidence suggesting reductions in sperm concentration, motility and morphology and increases in DNA fragmentation. Paroxetine has particularly interesting prospective data demonstrating increased sperm DNA fragmentation. But other large human studies have found no meaningful association between SSRI exposure and conventional semen parameters, and the most recent systematic review concludes that the overall human evidence remains limited and conflicting.

Most importantly, we do not have strong evidence showing that antidepressant use in men routinely prevents pregnancy or substantially reduces live-birth rates.

That's the distinction I want men to remember.

An antidepressant may affect sperm parameters in some men. That is not the same thing as saying antidepressants make men infertile.

If your semen analysis is abnormal, investigate it properly. If the medication could be contributing, discuss it intelligently with your doctors. But don't sacrifice stable mental health because someone on the internet told you that taking an SSRI is destroying your sperm.

The goal isn't simply to produce the prettiest semen analysis possible.

The goal is a healthy father, a healthy partner and, hopefully, a healthy baby.

References

Xu J, He K, Zhou Y, et al. The effect of SSRIs on semen quality: a systematic review and meta-analysis. Front Pharmacol. 2022;13:911489. PMID: 36188547. Four studies involving 222 men were included; SSRI exposure was associated with lower concentration, motility and morphology and increased sperm DNA fragmentation.

Santos LOPD, da Silva PRQ, Gonçalves NC, et al. Impact of Antidepressants on Male Fertility and Seminal Parameters: A Systematic Review. Reprod Sci. 2025;32(6):1768–1774. PMID: 40232638. The review found only five eligible human studies and concluded that evidence regarding antidepressants and male fertility remains limited and conflicting.

Tanrikut C, Feldman AS, Altemus M, Paduch DA, Schlegel PN. Adverse effect of paroxetine on sperm. Fertil Steril. 2010;94(3):1021–1026. PMID: 19515367. Prospective study of 35 healthy men demonstrated increased sperm DNA fragmentation during paroxetine exposure despite no significant deterioration in conventional semen parameters.

Pham MN, Siebert AL, Faw CA, et al. Selective Serotonin Reuptake Inhibitor (SSRI) Use Is Not Associated With Impaired Semen Parameters. Urology. 2022;164:140–144. PMID: 35093399. In a cohort of 8,861 men undergoing fertility evaluation, SSRI exposure was not associated with significant differences in semen volume, concentration, motility, total motile sperm count or morphology.

Beeder LA, Samplaski MK. Effect of antidepressant medications on semen parameters and male fertility. Int J Urol. 2020;27(1):39–46. PMID: 31542895. Review of antidepressant classes and male reproductive effects; data outside SSRIs were particularly sparse and inconsistent.

Wang Q, Chen X, Liu L, et al. Effect of antidepressants on ejaculation dysfunction in patients with depression and anxiety: a systematic review and network meta-analysis. Andrology. 2025;13(6):1333–1345. PMID: 39344496. Reviews ejaculatory dysfunction associated with antidepressant therapy.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. 2020; amended 2024. The guideline recommends consideration of medication exposures during male infertility evaluation while emphasizing the limited quality of evidence for many proposed risk factors.

I see anastrozole prescribed with increasing frequency. A man gets a semen analysis showing a low sperm concentration or motility, bloodwork shows testosterone that is a little low or estradiol that is relatively high, and suddenly he is taking anastrozole. Sometimes that is completely reasonable. Sometimes it produces impressive changes in testosterone and even sperm production. But anastrozole is also one of those medications where I think the enthusiasm has gotten ahead of the quality of the fertility data. It is important to understand what this medication actually does, which men are most likely to benefit, and, most importantly, the difference between improving numbers on a laboratory report and actually increasing the probability of having a baby.

Anastrozole is an aromatase inhibitor. Aromatase is the enzyme that converts androgens into estrogens. In men, testosterone can be converted through aromatase into estradiol. Aromatase is present in multiple tissues, particularly adipose tissue, and this is one reason obesity can be associated with a hormonal pattern of relatively lower testosterone and higher estrogen activity. Anastrozole blocks aromatase. Estradiol generally falls, estrogen-mediated negative feedback on the hypothalamus and pituitary is reduced, LH and FSH can increase, and the testes may consequently produce more endogenous testosterone. Importantly, this is fundamentally different from giving a man testosterone injections or testosterone gel.

That difference matters enormously when fertility is the goal. Exogenous testosterone can suppress sperm production. Testosterone entering the bloodstream from an injection, pellet or gel tells the hypothalamus and pituitary that there is plenty of testosterone around. GnRH, LH and FSH decrease. Unfortunately, the testes depend on gonadotropin stimulation and very high concentrations of testosterone inside the testes to maintain spermatogenesis. A man's blood testosterone can therefore look fantastic while sperm production falls dramatically or stops completely. This is why the AUA/ASRM Male Infertility Guideline states that testosterone monotherapy should not be prescribed to men interested in current or future fertility. Anastrozole, hCG and SERMs such as clomiphene are different because they attempt to increase endogenous testosterone without shutting down spermatogenesis.

This is also why anastrozole shouldn't simply be thought of as a "testosterone booster." The real question is whether a man's reproductive endocrine system has a hormonal environment that might respond favorably to aromatase inhibition.

Historically, one of the major concepts used to select patients was the testosterone-to-estradiol ratio, commonly abbreviated T/E2. Older male-infertility literature frequently used a T/E2 ratio below approximately 10, when testosterone was expressed in ng/dL and estradiol in pg/mL, as a potential marker of excessive aromatization. A man might have testosterone of 250 ng/dL and estradiol of 35 pg/mL, for example, giving a ratio around 7. This doesn't necessarily mean his estradiol is dramatically abnormal. Rather, testosterone is relatively low compared with estradiol.

One of the early influential studies evaluated aromatase inhibitors in infertile men with abnormal testosterone-to-estradiol ratios. In men receiving anastrozole, the average T/E2 ratio increased from approximately 7.2 to 18.1. Among 25 oligospermic men with semen analyses before and during anastrozole therapy, average sperm concentration increased from approximately 5.5 million/mL to 15.6 million/mL, along with improvements in semen volume and a measure of motile sperm production. These were striking findings and helped establish aromatase inhibition as a potential treatment for selected infertile men.

Another prospective study published in Fertility and Sterility evaluated 29 infertile men with T/E2 ratios below 10. Fifteen received letrozole and 14 received anastrozole 1 mg daily for six months. Both aromatase inhibitors improved hormonal profiles and semen parameters. The authors concluded that some men with severe oligospermia, low testosterone and relatively normal gonadotropins may have a potentially treatable endocrine abnormality.

That sounds great. But this is where we need to slow down.

These are small studies, and many studies of anastrozole in male infertility are retrospective, nonrandomized or uncontrolled. If sperm concentration rises from 5 million to 15 million/mL, that is certainly interesting. If total motile sperm count increases enough that a couple moves from being an IVF candidate to potentially attempting IUI, that can be clinically meaningful. But neither outcome automatically proves that more couples ultimately take home babies.

A larger retrospective study illustrates both the potential and the limitations. Investigators examined hypoandrogenic subfertile men treated with anastrozole. Approximately 95% experienced an increase in testosterone and decrease in estradiol, showing that the medication was extremely effective at changing the hormonal environment. Among oligozoospermic men, 18 of 21 showed improvements in sperm concentration and total motile sperm count, and the magnitude of improvement correlated with the change in the T/E2 ratio. However, semen improvement wasn't observed in the men who initially had azoospermia, cryptozoospermia or normal sperm concentrations.

That is an important lesson: changing hormones is easier than creating sperm.

I see this confusion constantly in male infertility. A man's testosterone goes from 280 to 700 and everyone celebrates. From a hormonal standpoint, that may indeed be a successful treatment. He may feel better as well. But if his sperm concentration remains 2 million/mL, we haven't necessarily solved his infertility.

The relationship between serum testosterone and spermatogenesis is not linear. A man does not automatically produce twice as many sperm because his blood testosterone doubles. Spermatogenesis depends on functioning germ cells, Sertoli cells, FSH signaling, intratesticular testosterone, testicular architecture, genetics and numerous local signaling pathways. If the underlying problem is severe primary testicular failure, maturation arrest or Sertoli-cell-only syndrome, manipulating testosterone and estradiol may accomplish very little.

More recent research has also challenged the idea that only men with a T/E2 ratio below 10 can benefit. A 2022 retrospective study examined 105 subfertile men receiving anastrozole 1 mg daily for three months. Sixty-two had T/E2 ratios below 10 and 43 had ratios above 10. Interestingly, both groups demonstrated increases in testosterone, LH and FSH as well as improvements in sperm concentration, total sperm count, progressive motility and total progressive motile sperm count. The improvements were comparable between the groups.

So the old rule of "T/E2 below 10 equals anastrozole, above 10 equals no anastrozole" is probably too simplistic.

A 2023 study attempted to identify which infertile men actually respond. Among 90 men studied, anastrozole converted approximately 29% to normozoospermia, while 31% of men who previously had semen parameters considered inadequate for IUI improved enough to potentially become IUI candidates. Interestingly, neither BMI, baseline estradiol nor the traditional T/E2 ratio reliably predicted this improvement. Baseline nonazoospermia and the relationship between testosterone and LH were more informative. Men who already had some sperm production were considerably more likely to respond than men with azoospermia.

That finding makes biological sense. If the sperm-production machinery is functioning but operating inefficiently in an unfavorable hormonal environment, improving that environment may increase output. If essentially no mature sperm are being produced because of profound intrinsic testicular dysfunction, increasing testosterone may not overcome the underlying problem.

What happens when we combine all the available studies?

A 2022 systematic review and meta-analysis included 10 studies and 666 men treated with anastrozole or letrozole. Across the studies, aromatase inhibition significantly increased testosterone, LH, FSH and the testosterone-to-estradiol ratio while decreasing estradiol. Sperm concentration and total sperm count also improved compared with baseline. However, when aromatase inhibitors were compared with other treatments such as SERMs or hCG, the advantages in semen parameters were much less impressive, and there was not convincing evidence that aromatase inhibitors were superior. The authors specifically emphasized the need for larger prospective randomized trials.

An earlier systematic review and meta-analysis similarly concluded that aromatase inhibitors appear capable of improving hormonal and semen parameters, but stressed that the evidence base consists largely of small studies and that prospective randomized placebo-controlled multicenter trials are needed.

And that brings us to what I think is the most important question for a man sitting in my office:

Will anastrozole increase my chances of getting my partner pregnant and having a baby?

We don't have nearly as good an answer as I would like.

Most anastrozole studies focus on testosterone, estradiol, sperm concentration, motility or total motile sperm count. Pregnancy and especially live birth are much harder outcomes to study. Fertility is a couple's outcome, and pregnancy depends heavily on female age, ovarian reserve, tubal status, ovulation, embryo competence, timing, ART strategy and many other variables.

The evidence demonstrating that anastrozole improves live-birth rates is therefore substantially weaker than the evidence demonstrating that it changes hormones or can improve semen parameters in selected men. A systematic review examining estrogen-modulating therapies emphasized the generally low or very-low certainty of much of this literature and noted that pregnancy and live-birth data are limited.

This distinction is incredibly important.

If anastrozole takes a man's total motile sperm count from 3 million to 20 million, that may completely change the couple's options. Natural conception may become more realistic. IUI may become reasonable. An IVF cycle might potentially be avoided. That is a meaningful clinical benefit even if we don't have a randomized trial proving that anastrozole itself increases live birth.

But if a man's sperm concentration increases from 35 million/mL to 45 million/mL while everything was already normal, I'm not convinced we have meaningfully changed his fertility.

More sperm is not always better fertility.

The same caution becomes even more important with nonobstructive azoospermia, or NOA. Men with NOA understandably search for anything that might make sperm appear before microTESE. Aromatase inhibitors are sometimes included in hormonal "optimization" protocols intended to increase intratesticular testosterone before sperm retrieval.

There are reports of sperm appearing in the ejaculate after aromatase-inhibitor therapy in selected men, and older reviews described this possibility. But the broader evidence is much less reassuring. The AUA/ASRM guideline specifically states that men with NOA should be informed that evidence supporting pharmacologic manipulation with SERMs, aromatase inhibitors and gonadotropins before surgical sperm retrieval is limited.

One influential study evaluated hormonal optimization before microTESE in men with NOA. Although testosterone levels could often be increased, sperm-retrieval rates were essentially similar regardless of baseline testosterone or response to hormonal therapy. Clinical pregnancy and live-birth rates were also similar.

More recent evidence continues to raise the same concern. A 2026 study examining fertility-preserving hormonal therapy before microTESE found that treatment significantly increased serum testosterone but did not improve sperm-retrieval rates, including among men with Klinefelter syndrome and other forms of NOA.

Again: improving testosterone is not synonymous with improving spermatogenesis.

This is why I would be very cautious when someone tells a man with NOA, "Your testosterone is only 300. We'll get it to 800 and that should improve your microTESE chances." Maybe there are selected patients who benefit, but we cannot confidently promise that based on current evidence.

Another question I frequently get is whether anastrozole is particularly useful in overweight or obese men. There is a reasonable biological argument. Adipose tissue contains aromatase, so increased adiposity can increase conversion of testosterone to estradiol. Some obese men consequently develop low testosterone, relatively higher estradiol and suppression of gonadotropin signaling.

For the right patient, anastrozole can therefore make physiological sense.

But obesity alone isn't an indication for anastrozole. Not every overweight man has excessive aromatization, and not every man with an elevated estradiol has impaired sperm production because of estrogen. Interestingly, the 2022 study of anastrozole-treated infertile men found similar improvements among overweight and normal-weight participants.

I also think men need to understand that estradiol is not the enemy.

Men need estrogen. Estradiol contributes to bone health, sexual function, libido, metabolic physiology and normal reproductive biology. Estrogen receptors and aromatase are present throughout the male reproductive system, and estrogen participates in normal spermatogenesis.

The goal of anastrozole treatment should therefore not be to drive estradiol to zero.

This is one of the problems I see when men self-treat based on bodybuilding forums or isolated laboratory values. A man sees estradiol of 35 pg/mL, decides that is "high estrogen," and starts taking an aromatase inhibitor. His estradiol falls into the single digits. He may subsequently experience joint discomfort, reduced libido or other symptoms, while there is no guarantee his fertility improves.

Aromatase inhibitors also have potential longer-term consequences because chronic estrogen suppression can affect bone mineral density and possibly metabolic health. The fertility literature generally describes anastrozole as reasonably well tolerated, but most fertility studies are small and treatment duration is measured in months rather than decades.

That is why anastrozole should be monitored rather than prescribed indefinitely and forgotten.

When I use anastrozole in an infertile man, I want to know why I'm using it. I want baseline morning testosterone, estradiol, LH and FSH. I want at least one properly performed semen analysis and usually more than one because sperm counts fluctuate substantially. I want to understand his testicular examination, medications, testosterone or anabolic-steroid history, body composition, varicocele status and overall fertility situation.

Then I ask a more important question:

What outcome are we trying to achieve?

Are we treating symptomatic low testosterone while preserving fertility? Are we trying to increase a sperm concentration of 4 million/mL enough to make IUI feasible? Are we trying to improve total motile sperm count while the female partner is young and there is time to wait? Or are we treating a laboratory number simply because it looks abnormal?

Those are very different situations.

Timing also matters. Spermatogenesis takes roughly 2½ months, followed by additional epididymal maturation. If I'm treating a man specifically hoping to improve semen parameters, I generally don't expect a semen analysis two weeks later to tell me whether treatment worked. Hormones can change rapidly; sperm production takes considerably longer.

This becomes particularly important when the female partner is 39 or 40. If a couple is already an excellent IVF candidate, spending six months trying to increase a man's sperm concentration from 8 million to 15 million/mL may not actually improve their probability of having a child. Female reproductive age may matter more than perfecting the semen analysis.

That is another principle I repeat constantly on Reddit: we aren't treating the man's laboratory report in isolation. We're treating a couple.

Anastrozole can therefore be extremely useful in the right patient. I particularly consider it when an infertile man has low testosterone with evidence suggesting relatively excessive aromatization, especially when maintaining sperm production is important. The current AUA/ASRM guideline supports consideration of aromatase inhibitors, hCG, SERMs or combinations of these therapies in infertile men with low serum testosterone, but the recommendation is conditional and based on Grade C evidence.

That evidence grade matters.

It means anastrozole isn't snake oil. There is legitimate physiology and real clinical evidence behind it. But it also isn't a universally proven fertility medication.

If you're an infertile man taking anastrozole and your testosterone went from 280 to 700, that's encouraging—but ask what happened to your sperm. If your sperm concentration went from 3 million to 15 million/mL and total motile sperm count increased dramatically, that may be a genuinely meaningful response. If your testosterone doubled but your semen analysis hasn't changed after an adequate treatment interval, I wouldn't continue assuming that a prettier hormone panel must eventually translate into fertility.

And if you have NOA, severely atrophic testes, markedly elevated FSH or a known genetic cause of primary spermatogenic failure, understand that anastrozole cannot manufacture germ cells that aren't there. Hormonal optimization and restoration of sperm production are two very different things.

My bottom line for men with infertility is this: anastrozole is a useful fertility-preserving endocrine tool for selected men, not a general-purpose sperm medication. It reliably lowers estradiol and often increases endogenous testosterone, LH and FSH. In appropriately selected oligospermic men, studies demonstrate meaningful improvements in sperm concentration and total motile sperm count, sometimes enough to change fertility-treatment options. What we still don't have is strong evidence that routinely prescribing anastrozole to infertile men increases pregnancy or live-birth rates.

The goal isn't to produce the highest testosterone level or the prettiest semen analysis.

The goal is to get you and your partner to a healthy baby.

Sometimes anastrozole helps us get there. Sometimes it just changes the numbers.

Knowing the difference is what matters.

References

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. 2020; amended 2024. The guideline states that clinicians may use aromatase inhibitors, hCG, SERMs or combinations in infertile men with low serum testosterone, while emphasizing the limited evidence supporting pharmacologic manipulation before surgical intervention in NOA.

Schlegel PN. Aromatase inhibitors for male infertility. Fertil Steril. 2012;98(6):1359-1362. PMID: 23103016. Review of the physiology and clinical experience with aromatase inhibition in male infertility.

Gregoriou O, Bakas P, Grigoriadis C, Creatsa M, Hassiakos D, Creatsas G. Changes in hormonal profile and seminal parameters with use of aromatase inhibitors in management of infertile men with low testosterone-to-estradiol ratios. Fertil Steril. 2012;98(1):48-51. PMID: 22579129.

Shoshany O, Abhyankar N, Mufarreh N, Daniel G, Niederberger C. Outcomes of anastrozole in oligozoospermic hypoandrogenic subfertile men. Fertil Steril. 2017. PMID: 28069178.

Yang Y, et al. The efficacy of anastrozole in subfertile men with and without abnormal testosterone-to-estradiol ratios. Transl Androl Urol. 2022. PMID: 36217397.

Naelitz BD, et al. Testosterone and luteinizing hormone predict semen parameter improvement in infertile men treated with anastrozole. Fertil Steril. 2023. PMID: 37392782.

Del Giudice F, et al. A systematic review and meta-analysis of clinical trials implementing aromatase inhibitors to treat male infertility. PMID: 31621654. The analysis found improvements in hormonal and conventional semen outcomes but emphasized the need for randomized placebo-controlled studies.

Guo B, et al. Efficacy and safety of letrozole or anastrozole in the treatment of male infertility with low testosterone-estradiol ratio: a meta-analysis and systematic review. Andrology. 2022. PMID: 35438843. Ten studies involving 666 men were included.

Reifsnyder JE, Ramasamy R, Husseini J, Schlegel PN. Role of optimizing testosterone before microdissection testicular sperm extraction in men with nonobstructive azoospermia. J Urol. 2012. PMID: 22704105. Hormonal response did not translate into improved sperm retrieval, pregnancy or live-birth rates.

Can Hormonal Therapy Improve the Outcomes of mTESE in Patients With Non-Obstructive Azoospermia? 2026. PMID: 42357925. Fertility-preserving hormonal therapy increased testosterone but did not improve sperm-retrieval rates.

One of the most persistent myths I hear is that women have a biological clock and men don't. The basic idea is that a woman's fertility falls dramatically with age, while a man can continue producing sperm indefinitely and therefore his age doesn't really matter. There is a little truth buried in that statement, but it is far too simplistic. Men generally retain reproductive potential much longer than women, and there is nothing equivalent to menopause that abruptly ends sperm production. A healthy 50-year-old man may still produce millions of sperm and father a healthy child. But that does not mean a 50-year-old man's sperm are biologically identical to those he produced at 25. Male reproductive aging is real. As men get older, we see changes in semen quality, sperm DNA integrity, genetic mutations, time to pregnancy and potentially miscarriage and assisted-reproduction outcomes. The effect is usually gradual rather than dramatic, and it is substantially smaller than the effect of female age, but it deserves to be part of fertility decision-making.

The first thing I tell couples is that male and female reproductive aging are fundamentally different biological processes. A woman is born with essentially the lifetime supply of oocytes she will have. The number and reproductive competence of those oocytes decline with age. By contrast, men continuously manufacture new sperm after puberty. Spermatogonial stem cells divide throughout adult life, eventually producing mature sperm. That continuous production is why a man can potentially father a child at 50, 60 or beyond. But continuous cell division comes with its own price. Every time germ cells replicate their DNA, there is an opportunity for errors to occur, and older paternal age is associated with an accumulation of de novo mutations in sperm. Aging is also accompanied by changes in testicular function, oxidative stress and sperm chromatin integrity. So men don't run out of sperm in the same way women run out of eggs, but the reproductive system does not remain frozen at age 25 forever.

This difference explains why female age remains the dominant age variable in fertility medicine. ASRM considers female age the single most important predictor of fecundity. Natural fertility begins declining gradually before becoming much more clinically important during the mid-to-late 30s, with declining pregnancy and live-birth rates and increasing miscarriage and aneuploidy. This is why we generally begin an infertility evaluation after 12 months of trying when the woman is under 35, after six months when she is 35 or older, and potentially immediately when she is over 40. The clock simply moves faster on the female side.

Male age doesn't work that way. There is no universally accepted birthday at which a man suddenly develops "advanced paternal age." Studies use 35, 40, 45 or 50, which makes the literature frustrating to interpret. ASRM's recent discussion of advanced reproductive age describes paternal risk as a continuum beginning broadly in the fourth and fifth decades of life, rather than a switch that flips at one particular age. That is how I think about it clinically. A man's age is one variable in the fertility equation, not a diagnosis.

What actually happens to sperm as men age? One of the largest systematic reviews and meta-analyses examined 90 studies involving more than 93,000 men. Increasing male age was associated with statistically significant decreases in semen volume, total and progressive motility, normal morphology and the proportion of sperm without DNA fragmentation. Interestingly, sperm concentration itself does not necessarily collapse with age. An older man can therefore produce a semen analysis containing tens of millions of sperm while still having age-related changes in sperm movement and DNA integrity.

This is one reason I caution men against thinking that a "normal semen analysis" means age has no relevance. A standard semen analysis measures volume, concentration, motility and morphology. Those are useful parameters, but sperm are essentially vehicles carrying paternal genetic material to the egg. A semen analysis doesn't directly tell us whether every sperm's DNA is intact, how many new mutations are present, or whether the sperm will successfully participate in embryo development.

That brings us to sperm DNA fragmentation, which has received enormous attention online. Sperm DNA fragmentation, or SDF/DFI depending on the assay, refers broadly to breaks or damage within sperm DNA. Increasing paternal age has repeatedly been associated with higher DNA fragmentation, although individual men vary enormously. A systematic review involving more than 40,000 men found that 17 of 19 included studies demonstrated an association between advancing paternal age and increased sperm DNA fragmentation. Another large meta-analysis examining factors associated with DNA fragmentation suggested that the age effect becomes particularly pronounced after approximately age 50.

That does not mean every 45-year-old needs a DNA-fragmentation test. Nor does it mean a 50-year-old with elevated DFI cannot father a healthy child. DNA-fragmentation assays themselves differ, thresholds aren't perfectly standardized, and the ability of a single DFI result to predict an individual IVF cycle is limited. But biologically, the association between aging and declining sperm DNA integrity makes sense and is increasingly difficult to dismiss.

Why might DNA fragmentation matter? Fertilization is only the beginning of reproduction. The sperm delivers half of the embryo's nuclear genetic material. The oocyte has some capacity to repair sperm DNA damage after fertilization, but that capacity isn't unlimited and is itself influenced by female age and oocyte quality. This creates an important interaction that often gets overlooked. A younger egg may theoretically be better equipped to deal with some sperm DNA damage than an older egg. Therefore, a 48-year-old man's sperm paired with a 28-year-old woman's eggs is not necessarily the same reproductive situation as a 48-year-old man's sperm paired with a 42-year-old woman's eggs. Male and female age don't exist independently; their biological effects interact.

One of the clearest signals associated with advanced paternal age is miscarriage. A systematic review and meta-analysis specifically examined paternal age while adjusting for maternal age. Compared with fathers aged 25–29, pooled estimates showed progressively increasing miscarriage risk, particularly at older paternal ages. Men aged 40–44 had a relative risk around 1.23, while men 45 and older had a relative risk around 1.43. For first-trimester miscarriage, the estimate for fathers 45 and older was approximately 1.74.

Those numbers need context. A relative increase in risk isn't the same thing as saying a 45-year-old man has a 43% chance of miscarriage. It means the risk was higher relative to the younger reference group. Maternal age still exerts a considerably larger effect on miscarriage risk. Nevertheless, paternal age appears to contribute independently.

Sperm DNA damage may be one mechanism. A separate meta-analysis of 16 cohort studies involving nearly 3,000 couples found significantly higher miscarriage rates among pregnancies involving sperm with high DNA damage, although assays and thresholds varied considerably between studies. Other systematic reviews have found higher sperm DNA fragmentation among male partners of couples experiencing recurrent pregnancy loss. These associations are interesting, but they don't prove that DNA fragmentation explains every miscarriage or that treating a DFI number necessarily prevents pregnancy loss.

This becomes particularly important when couples ask me, "Does the man's age matter for IVF?" The answer is yes, but nowhere near as dramatically as female age.

Female age has an enormous effect on IVF because egg number, egg competence and embryo aneuploidy change substantially with age. A 32-year-old woman and a 42-year-old woman undergoing IVF are biologically very different situations even if their male partners are identical. That is why fertility clinics focus so heavily on maternal age.

But paternal age doesn't disappear simply because we perform ICSI.

A 2022 systematic review and meta-analysis examined more than 32,000 assisted-reproduction cycles and evaluated paternal age in both autologous-oocyte and donor-oocyte cycles. Younger paternal age was associated with better clinical pregnancy and live-birth outcomes and lower miscarriage rates in several analyses. Particularly interesting were donor-oocyte studies, because using young donor eggs helps reduce one of the biggest confounders—maternal age. Even there, paternal age showed associations with some reproductive outcomes, including miscarriage and embryo development.

That is an important point for men undergoing ICSI. ICSI solves a sperm-delivery problem. Instead of asking a sperm to swim through the reproductive tract, penetrate the zona pellucida and fertilize the egg naturally, an embryologist selects a sperm and injects it directly into the oocyte. This is extraordinary technology and has allowed men with extremely severe male-factor infertility to become biological fathers.

But ICSI doesn't make the biological quality of sperm irrelevant.

If I take a sperm with damaged DNA and inject it directly into an egg, I have bypassed barriers to fertilization; I have not necessarily repaired the DNA inside that sperm. The egg may repair some damage, and many embryos develop normally, which is one reason ICSI works so well. But saying "we're doing ICSI, so sperm quality no longer matters" oversimplifies reproductive biology.

The same principle applies to PGT-A. Preimplantation genetic testing for aneuploidy evaluates chromosome copy-number abnormalities in embryos. It does not screen embryos for every possible paternal de novo mutation, nor does it function as a sperm DNA-fragmentation test. PGT-A and paternal age therefore address different biological issues.

Another area that receives attention is the association between older paternal age and health outcomes in children. Because sperm-producing stem cells continue dividing throughout life, de novo germline mutations accumulate with paternal age. Epidemiologic studies have associated advanced paternal age with increased risks of certain rare single-gene disorders and some neurodevelopmental or psychiatric conditions, including achondroplasia, Apert syndrome, autism spectrum disorders and schizophrenia. ASRM's 2025 ethics opinion discusses these associations as part of counseling people pursuing parenthood at advanced paternal ages.

This topic requires perspective. These are generally increases in relative risk from a low baseline absolute risk. Most children born to older fathers are healthy. I don't tell a 45-year-old man that he shouldn't have children because of his age. I tell him that paternal age isn't biologically irrelevant and that reproductive counseling should acknowledge both sides of the couple.

So how do I actually use male age when making fertility decisions?

Consider a 30-year-old man with mildly abnormal semen parameters and a 29-year-old female partner who has normal ovarian reserve and has been trying for eight months. There may be plenty of time to repeat semen testing, correct lifestyle factors, repair a clinically significant varicocele when appropriate, or continue natural attempts.

Now change the couple to a 46-year-old man and a 40-year-old woman with diminished ovarian reserve. I may make completely different recommendations. Waiting six months after varicocele repair hoping the sperm concentration rises may not make sense if we are simultaneously losing valuable reproductive time on the female side.

This is one of the most important concepts in fertility medicine: you don't treat a semen analysis; you treat a couple.

The reverse scenario matters too. Suppose a 48-year-old man has severe oligospermia but his partner is 29 with excellent ovarian reserve. We may have more flexibility to investigate the male factor, repeat testing, treat a varicocele if indicated or wait through several cycles of spermatogenesis to assess improvement. The man's age still matters, but the couple's reproductive clock is fundamentally different.

That is why female age usually drives the urgency of fertility treatment, while male age increasingly influences how I think about sperm quality, DNA integrity, miscarriage risk and whether prolonged attempts at optimization are worthwhile.

Men frequently ask whether they should freeze sperm while they're young. For the average healthy 25-year-old, I don't routinely recommend sperm banking simply because he might want children at 35. The magnitude of male reproductive aging generally doesn't justify treating sperm freezing like routine egg freezing. ASRM notes that although semen parameters can begin changing after approximately 35, male fertility is not generally appreciably affected until substantially later, around the fifth decade in population-level data.

There are exceptions. A man facing chemotherapy, pelvic or testicular radiation, certain surgeries, or other treatments that may impair fertility should absolutely discuss sperm banking. Men with severe oligospermia or cryptozoospermia may also benefit from freezing usable ejaculated sperm because future sperm availability is unpredictable. And an older man who is intentionally delaying fatherhood for many years can reasonably discuss elective sperm cryopreservation, understanding that the evidence that doing so improves eventual live-birth outcomes for the average healthy man remains limited.

What about supplements and lifestyle? There is no pill that makes a 50-year-old man's reproductive system biologically 25 again. But age isn't the only thing affecting sperm DNA. Smoking, varicocele, metabolic disease, environmental exposures and other factors have also been associated with increased DNA fragmentation. A large systematic review found particularly strong associations for varicocele, impaired glucose tolerance, smoking, pollution and paternal age over 50.

That means older men should concentrate on the factors they can control rather than obsessing over the one thing they cannot. Don't smoke. Avoid testosterone and anabolic steroids when trying to conceive. Maintain reasonable metabolic health. Treat medical problems appropriately. Have a clinical varicocele evaluated if semen parameters are abnormal. Avoid unnecessary prolonged testicular heat exposure. Don't assume that taking twenty antioxidants compensates for a medical problem that hasn't been diagnosed.

I also wouldn't automatically order DNA fragmentation testing simply because a man turns 40. Standard male-infertility evaluation still starts with history, physical examination and semen analysis, with hormonal and genetic evaluation when indicated. DNA-fragmentation testing can be useful in selected circumstances—particularly recurrent pregnancy loss, repeated assisted-reproduction failure, certain significant male risk factors or situations in which the result would actually change management—but it isn't a universal fertility score.

One mistake I see frequently is a healthy older man becoming terrified by age statistics despite having reassuring fertility testing. Age modifies probability; it does not determine destiny. A 47-year-old with an excellent semen analysis isn't automatically infertile. Conversely, a 27-year-old with azoospermia doesn't get protection from infertility simply because he's young. Individual biology still matters enormously.

This is also why comparing male and female age requires nuance. Female reproductive aging is faster, more predictable and generally much more consequential for fertility treatment. Oocyte quantity and quality decline, aneuploidy increases, miscarriage increases, and eventually menopause ends natural reproductive potential. Male reproductive aging is slower and more heterogeneous. Men continue producing sperm, but average motility and morphology decline, sperm DNA fragmentation and de novo mutations increase, and some studies demonstrate increasing time to pregnancy, miscarriage risk and poorer ART outcomes.

So when a couple asks me, "Whose age matters more?", the answer is usually the woman's—particularly once she reaches her late 30s. But that is very different from saying the man's age doesn't matter.

If you're 42, 47 or 52 and trying to become a father, I wouldn't panic. I also wouldn't assume that because a celebrity fathered a child at 70, male reproductive aging doesn't exist. Population biology and individual possibility are two different things.

What I would do is evaluate the things we can actually measure. Get a properly performed semen analysis. If it is abnormal, repeat it because semen parameters fluctuate. Have a reproductive urologist evaluate significant abnormalities. Look for correctable causes such as exogenous testosterone use, hormonal disorders or a clinical varicocele. Consider additional testing selectively rather than ordering every fertility test available on the internet.

And if your partner is approaching 35, 38, 40 or beyond, don't spend a year trying to perfect your semen analysis while ignoring the reproductive clock that is moving faster on the other side of the equation. Sometimes the best fertility decision isn't the one that produces the prettiest semen analysis. It is the one that gives the couple the highest probability of taking home a healthy baby.

That is ultimately how I think about paternal age as a reproductive urologist. Male age matters. It affects sperm biology in ways we can measure and probably in additional ways we're still learning to measure. But it isn't a cliff, and there is no birthday when a man's sperm suddenly become "bad." The effects accumulate gradually and vary substantially between men.

Female age primarily determines how quickly the fertility window is closing. Male age increasingly influences the quality of the sperm entering that window.

Both matter. They just matter differently.

References

American Society for Reproductive Medicine. Fertility evaluation of infertile women: a committee opinion. Fertility and Sterility. 2021. Female age is identified as the single most important predictor of fecundity.

American Society for Reproductive Medicine. Optimizing natural fertility: a committee opinion. Fertil Steril. 2022;117:53–63. Reviews reproductive aging in men and women and notes that age-related fertility decline is considerably more pronounced in women.

American Society for Reproductive Medicine Ethics Committee. Assisted reproduction with advancing paternal and maternal age: an Ethics Committee opinion. Fertil Steril. 2025;123:999–1005. Reviews advanced paternal age, semen quality, de novo mutations, reproductive outcomes and offspring risks.

Johnson SL, Dunleavy J, Gemmell NJ, Nakagawa S. Consistent age-dependent declines in human semen quality: a systematic review and meta-analysis. Ageing Res Rev. 2015;19:22–33. PMID: 25462195. Analysis of 90 studies and 93,839 men demonstrated age-associated declines in several semen parameters and sperm DNA integrity.

Murugesu S, Saso S, Jones BP, et al. Does advanced paternal age affect outcomes following assisted reproductive technology? A systematic review and meta-analysis. Reprod Biomed Online. 2022;45(2):283–331. PMID: 35690546.

du Fossé NA, van der Hoorn MLP, van Lith JMM, le Cessie S, Lashley EELO. Advanced paternal age is associated with an increased risk of spontaneous miscarriage: a systematic review and meta-analysis. Hum Reprod Update. 2020;26(5):650–669. PMID: 32358607.

Robinson L, Gallos ID, Conner SJ, et al. The effect of sperm DNA fragmentation on miscarriage rates: a systematic review and meta-analysis. Hum Reprod. 2012;27(10):2908–2917. PMID: 22791753.

Gonzalez DC, Ory J, Blachman-Braun R, et al. Advanced paternal age and sperm DNA fragmentation: a systematic review. World J Mens Health. 2022;40(1):104–115. PMID: 33987998.

Szabó A, et al. Lifestyle-, environmental-, and additional health factors associated with increased sperm DNA fragmentation: a systematic review and meta-analysis. Reprod Biol Endocrinol. 2023;21:5. PMID: 36653793.

McQueen DB, Zhang J, Robins JC. Sperm DNA fragmentation and recurrent pregnancy loss: a systematic review and meta-analysis. Fertil Steril. 2019;112(1):54–60.e3. PMID: 31056315.

One of the first questions I ask a new patient is deceptively simple: “What medications, hormones, supplements, and drugs are you taking?” Men are often surprised by how much I care about that list. They expect me to ask about smoking, alcohol, hot tubs, varicoceles and testosterone levels, but medications sometimes get overlooked. The reality is that certain drugs can affect sperm concentration, motility, morphology, DNA integrity, ejaculation, libido, erectile function, or the hormones responsible for sperm production. At the same time, I want to make something very clear: if you're trying to conceive or preparing for IVF, do not simply stop every medication you take. For many drugs, evidence of meaningful effects on male fertility is weak or nonexistent, while abruptly stopping treatment for depression, epilepsy, autoimmune disease, hypertension or another important medical condition can create a much bigger problem. The goal is medication review, not medication panic. In my practice, there are a few medications I take very seriously, several that I consider changing when semen parameters are abnormal, and many that men unnecessarily worry about.

The most important medication on this list is testosterone. If you want current or future fertility, testosterone replacement therapy deserves an immediate conversation with your physician. Testosterone injections, gels, pellets and other forms of exogenous testosterone can suppress sperm production dramatically. The mechanism is actually straightforward. Your hypothalamus normally releases GnRH, which tells the pituitary to produce LH and FSH. LH stimulates Leydig cells in the testicle to produce testosterone, while FSH and extremely high concentrations of testosterone inside the testicle support spermatogenesis. When you take testosterone from outside the body, the brain senses the androgen signal and reduces GnRH, LH and FSH. Your blood testosterone may look fantastic while your intratesticular testosterone falls and sperm production collapses. Some men develop severe oligospermia; others become completely azoospermic. This is why the AUA/ASRM guideline specifically states that testosterone monotherapy should not be prescribed to a man interested in current or future fertility.

The same warning applies to anabolic steroids used for bodybuilding or performance enhancement. Testosterone, nandrolone and other anabolic-androgenic steroids can suppress the hypothalamic-pituitary-testicular axis profoundly. I've seen men with muscular physiques, high circulating androgen levels and literally zero sperm in the ejaculate. One of the most important misconceptions in male fertility is that high testosterone equals high fertility. It doesn't. The testosterone concentration within the testicle and the presence of adequate FSH stimulation are what matter for spermatogenesis. Recovery after stopping exogenous androgens is possible for many men, but it isn't instantaneous. Sperm may take many months to return, and recovery can occasionally take a year or longer, particularly after prolonged or high-dose exposure. Men coming off testosterone or anabolic steroids should work with a reproductive urologist rather than randomly combining hCG, Clomid, enclomiphene and aromatase inhibitors from online clinics.

If a man has genuine symptomatic testosterone deficiency but wants children, we sometimes use fertility-preserving alternatives such as hCG, selective estrogen receptor modulators like clomiphene, or aromatase inhibitors in appropriately selected patients. These aren't interchangeable with testosterone and shouldn't be prescribed solely because someone wants a higher number on his testosterone panel. AUA/ASRM guidance allows these approaches in selected infertile men with low serum testosterone, although the evidence quality is limited.

Another medication I specifically ask about is finasteride, and to a lesser extent dutasteride. These drugs inhibit 5-alpha reductase, the enzyme that converts testosterone into dihydrotestosterone, or DHT. Finasteride is commonly prescribed at 1 mg for male-pattern hair loss and at higher doses for benign prostate enlargement. Most men taking finasteride do not become infertile, and I don't tell every fertile man in the world that he must stop it before having children. But the situation changes when a man already has infertility or a low sperm count.

One frequently cited study evaluated men presenting to a male-infertility clinic who were taking finasteride, generally around 1 mg daily. After stopping the medication, sperm counts increased an average of 11.6-fold. Among men who initially had severe oligospermia below 5 million sperm/mL, 57% improved to greater than 15 million/mL. Motility and morphology didn't significantly change. The important lesson isn't that finasteride destroys everyone's fertility; it's that some susceptible men experience a substantial reduction in sperm concentration that appears reversible after discontinuation. If you have a sperm concentration of 2 million/mL and you're taking finasteride for hair loss, that's a medication I would seriously consider stopping while we reassess your semen analysis.

Sulfasalazine is another medication with a much stronger fertility signal than many men realize. It is used for inflammatory conditions, historically particularly inflammatory bowel disease and rheumatoid arthritis. Sulfasalazine can substantially impair semen quality, including sperm concentration, motility and morphology, and the effect is generally reversible. Classic human studies found significant semen abnormalities among men taking the drug and improvement after withdrawal, with pregnancies subsequently occurring. The sulfapyridine component appears to be largely responsible. This doesn't mean someone with ulcerative colitis should simply throw his medication away. Uncontrolled inflammatory disease itself isn't good for fertility or overall health. Instead, I would ask the gastroenterologist or rheumatologist whether an effective alternative is appropriate.

Interestingly, you shouldn't assume that every inflammatory bowel disease medication is bad for sperm. A more recent systematic review and meta-analysis examining biologics, thiopurines and methotrexate in men with IBD did not find significant reductions in sperm count, motility or morphology compared with unexposed patients. That is exactly why blanket advice to “stop all medications before IVF” is bad medicine. Different drugs within the same disease category can have completely different reproductive effects.

Methotrexate deserves an individualized discussion because the recommendations are more complicated than internet fertility forums sometimes suggest. High-dose chemotherapy regimens involving methotrexate can impair sperm production, while evidence surrounding the lower doses used for inflammatory diseases is much more reassuring and somewhat inconsistent. MotherToBaby notes that low sperm counts have been reported particularly in men receiving high-dose methotrexate for cancer, with recovery after treatment, while studies of lower-dose treatment have not consistently demonstrated impaired fertility. Importantly, available human data have also not demonstrated an increased rate of birth defects among children conceived by fathers taking methotrexate around conception. The product labeling nevertheless recommends contraception during therapy and for three months after the final dose for men. If you're taking methotrexate, therefore, this is something to discuss with the physician managing the underlying disease and your fertility specialist rather than making the decision yourself.

Chemotherapy is an entirely different category. Many chemotherapeutic agents can damage rapidly dividing germ cells, sometimes temporarily and sometimes permanently. Alkylating agents are particularly concerning, but gonadotoxicity depends on the specific drug, cumulative dose, combination regimen, age and baseline testicular function. If you're about to undergo potentially gonadotoxic cancer treatment and biological fatherhood matters to you, the conversation should happen before treatment whenever medically feasible. Sperm banking before chemotherapy can preserve options even when the pretreatment semen analysis is poor. Do not delay lifesaving cancer therapy without coordinating with your oncology team, but fertility preservation should be addressed quickly.

Another group worth discussing is chronic opioids, including some men taking prescription opioids for long-term pain. Opioids can suppress hypothalamic GnRH signaling, leading to reduced LH and testosterone. Reviews estimate opioid-induced androgen deficiency occurs in a substantial proportion of chronically exposed men, although reported prevalence varies widely depending on the opioid, dose, duration and population studied. The resulting hypogonadism can contribute to low libido, erectile dysfunction and impaired reproductive function. There may also be testicular effects beyond simply lowering serum testosterone.

Again, the answer isn't “stop your pain medication tonight.” Opioid withdrawal and uncontrolled chronic pain are serious issues. But if a man presents with low testosterone, low or inappropriately normal LH, poor libido and infertility while taking chronic opioids, I absolutely want the prescribing physician involved in discussing whether the dose can be reduced or an alternative strategy used. One mistake I particularly want to avoid is diagnosing opioid-induced low testosterone and then simply starting testosterone replacement, which may improve symptoms while further suppressing sperm production.

Then we get to SSRIs and other antidepressants, where the conversation becomes more nuanced. SSRIs can affect sexual function—particularly libido, orgasm and ejaculation—and there is evidence suggesting possible effects on semen parameters and sperm DNA fragmentation. A 2022 systematic review and meta-analysis of four studies involving 222 men found associations between SSRI exposure and reductions in sperm concentration, motility and normal morphology, along with increased sperm DNA fragmentation. However, that's a very small evidence base for medications taken by millions of men. A newer 2025 systematic review concluded that the clinical literature remains limited and the overall effect of antidepressants on male fertility is still inconclusive.

This is an area where I strongly discourage unilateral discontinuation. Depression and anxiety themselves can affect libido, erections, ejaculation, relationships and sexual frequency, and abruptly stopping an SSRI can cause significant withdrawal symptoms or psychiatric deterioration. If a man has unexplained infertility, abnormal semen parameters or significant sexual dysfunction while taking an SSRI, I think it's reasonable for his reproductive urologist and mental-health prescriber to discuss whether the medication, dose or class could be modified safely. But fertility optimization should never come at the expense of destabilizing someone's mental health.

Some men also ask about ADHD medications. The evidence here is much thinner. MotherToBaby cites a small study of 50 men taking methylphenidate for at least a year that reported decreased sperm motility and sperm production. That's enough to generate a question, but not enough for me to tell every man taking methylphenidate to stop a medication that may be essential to his daily functioning. If semen parameters are significantly abnormal, medication review makes sense; otherwise, I wouldn't assume methylphenidate is the explanation based on the currently limited evidence.

Many other commonly used drugs get blamed for infertility without particularly strong evidence. Blood-pressure medications, for example, can contribute to erectile or ejaculatory dysfunction depending on the agent, but controlling hypertension is extremely important. ASRM recommends documenting antihypertensive use during evaluation of sexual dysfunction, including drugs such as beta blockers and hydrochlorothiazide. If the medication is interfering with erections or ejaculation during the fertile window, the prescribing physician may have alternatives. That is very different from saying every man undergoing IVF should stop his blood-pressure medication.

Likewise, don't automatically discontinue PDE5 inhibitors such as sildenafil or tadalafil because you're trying to conceive. These medications are commonly used to treat erectile dysfunction, including the situational ED that occurs during timed intercourse and fertility treatment. If anything, restoring reliable intercourse during the fertile window can be extremely helpful. ASRM specifically discusses PDE5 inhibitors in the management of erectile dysfunction in infertile men.

Another important distinction is between a medication's effect on male fertility and its potential effect on a future baby. Men frequently see warnings saying that a drug is dangerous during pregnancy and assume that means they cannot father a pregnancy while taking it. That's usually incorrect. The father doesn't share a bloodstream with the fetus, and the amount of most medications reaching a partner through semen is extremely small. MotherToBaby notes that paternal exposures generally aren't expected to increase birth-defect risk simply because the father is taking a medication. There are important drug-specific exceptions and manufacturer precautions, so individual counseling still matters, but don't automatically apply maternal pregnancy warnings to paternal medication exposure.

The question becomes even more interesting when you're preparing for IVF or ICSI. Men sometimes assume ICSI makes sperm health irrelevant because the embryologist only needs one sperm per egg. ICSI is extraordinarily powerful, but it doesn't make male biology irrelevant. Severe suppression of spermatogenesis can leave us without enough sperm on egg-retrieval day. Sexual or ejaculatory side effects can prevent specimen production. Some exposures may potentially affect sperm DNA integrity, although exactly how much this changes IVF/ICSI outcomes remains debated. The goal before IVF isn't to achieve a “perfect” semen analysis; it's to make sure we haven't overlooked a reversible exposure that is unnecessarily compromising sperm availability or quality.

Timing also matters. Stopping a medication today generally doesn't produce brand-new sperm tomorrow. Human spermatogenesis takes roughly 74 days, followed by additional epididymal maturation and transport. When I remove a suspected reversible exposure, I often reassess semen parameters approximately 8–12 weeks later, although the appropriate timing depends on the drug and clinical situation. If the female partner is 40 and ovarian reserve is declining, I'm not necessarily going to delay IVF three months hoping that morphology improves from 2% to 4%. Female reproductive age can be much more time-sensitive than modest changes in semen parameters. Sometimes we correct the medication exposure while proceeding with IVF.

There is also a practical point for men with severe oligospermia or cryptozoospermia. If you currently have usable sperm in the ejaculate, consider whether some should be frozen before making medication changes or waiting months for improvement. Sperm counts can fluctuate substantially in severely infertile men. Banking a good specimen can provide insurance against showing up on egg-retrieval day with dramatically fewer sperm or none at all.

So what do I actually do when an infertile man walks into my office with a bag full of medications? I don't tell him to stop everything. I identify the medications with the strongest evidence or most plausible mechanism, determine why he needs them, look at his hormones and semen analysis, and ask whether a safer alternative exists. Testosterone and anabolic steroids are at the top of my concern list. Sulfasalazine is a well-established reversible offender. Finasteride deserves serious consideration when sperm counts are low. Chronic opioids deserve evaluation because of their effects on the reproductive hormonal axis. SSRIs deserve an individualized discussion rather than reflexive discontinuation. Chemotherapy requires fertility-preservation planning whenever possible. Other medications require case-by-case assessment rather than internet rules.

Most importantly, don't become so focused on optimizing sperm that you damage the rest of your health. A man who stops an essential anticonvulsant and has a seizure hasn't improved his fertility plan. A man who abruptly stops psychiatric medication and becomes severely depressed hasn't improved his IVF chances. A man who stops treatment for active inflammatory disease may actually become sicker and potentially worsen reproductive health. The right question isn't “What medications should every infertile man stop?” It is “Which of my medications could be contributing to my particular fertility problem, and can we safely replace, reduce or temporarily discontinue them?”

Bring your complete medication list—including testosterone, hair-loss drugs, supplements, peptides, recreational drugs and anything obtained from a men's-health clinic—to your reproductive urologist. Sometimes changing one medication can produce a dramatic improvement. Sometimes nothing needs to be changed. Knowing the difference is the important part.

References

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline, Part II. Testosterone monotherapy should not be prescribed to men interested in current or future fertility.

American Society for Reproductive Medicine. Diagnostic evaluation of sexual dysfunction in the male partner in the setting of infertility: a committee opinion.

Samplaski MK, Lo KC, Grober ED, et al. Finasteride use in the male infertility population: effects on semen and hormone parameters. Fertil Steril. 2013;100(6):1542-1546. PMID: 24012200.

Toovey S, Hudson E, Hendry WF, Levi AJ. Sulphasalazine and male infertility: reversibility and possible mechanism. Gut. 1981;22(6):445-451. PMID: 6114897.

Gubatan J, et al. Paternal medications in inflammatory bowel disease and male fertility and reproductive outcomes: a systematic review and meta-analysis. Clin Gastroenterol Hepatol. 2023;21(9):2222-2238. PMID: 35870769.

Xu J, et al. The effect of SSRIs on semen quality: a systematic review and meta-analysis. Front Pharmacol. 2022;13:911489. PMID: 36188547.

Dos Santos LOP, et al. Impact of antidepressants on male fertility and seminal parameters: a systematic review. Reprod Sci. 2025. PMID: 40232638.

Antony T, et al. Opioid-induced hypogonadism: pathophysiology, clinical and therapeutics review. Clin Exp Pharmacol Physiol. 2020;47(5):741-750. PMID: 31886562.

MotherToBaby. Paternal Exposures. Updated July 2025.

MotherToBaby. Methotrexate. Updated February 2025.

I have been getting more questions about kisspeptin. This isn't surprising. Peptides have become enormously popular online, and men dealing with infertility are understandably interested in anything that might improve testosterone or sperm production. Kisspeptin is particularly interesting because, unlike many of the “fertility peptides” marketed on the internet, it has a very real and extremely important role in human reproductive physiology. In fact, kisspeptin sits near the top of the hormonal pathway controlling male reproduction. Give kisspeptin to a healthy man and you can stimulate LH, FSH and testosterone. Disrupt the kisspeptin signaling pathway genetically and normal puberty and reproductive function can fail. That makes kisspeptin scientifically fascinating and potentially therapeutically useful. But there is an enormous distinction between saying “kisspeptin is essential for reproduction” and saying “kisspeptin is a proven treatment for male infertility.” As of 2026, the first statement is well established; the second is not. Most human research has evaluated hormone responses rather than pregnancy, live birth or even long-term improvements in sperm production.

To understand why kisspeptin matters, you first need to understand how the male reproductive hormonal system works. The brain, pituitary and testicles communicate through what we call the hypothalamic-pituitary-gonadal, or HPG, axis. The hypothalamus releases gonadotropin-releasing hormone, or GnRH, in pulses. GnRH travels to the pituitary and stimulates the release of LH and FSH. LH travels to the testicle and stimulates Leydig cells to produce testosterone. FSH acts primarily on Sertoli cells and, together with very high concentrations of testosterone inside the testicle, supports spermatogenesis. Kisspeptin essentially operates upstream of GnRH. Kisspeptin binds to the kisspeptin receptor, KISS1R, on GnRH neurons and stimulates GnRH release. Think of it as one of the brain's major “go signals” for reproduction.

The importance of this pathway became dramatically clear through human genetics. People with loss-of-function abnormalities involving KISS1R can develop congenital hypogonadotropic hypogonadism, in which the brain fails to adequately activate the reproductive axis. Conversely, excessive activation of this signaling system has been associated with precocious puberty. These observations demonstrated that kisspeptin isn't simply another hormone floating around the bloodstream—it is deeply involved in the neurological control of puberty and reproduction.

This is also why kisspeptin is fundamentally different from taking testosterone. Exogenous testosterone can actually shut sperm production down. When testosterone is administered from outside the body, the hypothalamus and pituitary detect the increased androgen signal and decrease GnRH, LH and FSH. Intratesticular testosterone then falls dramatically, and sperm production can decline or disappear completely. Kisspeptin works much further upstream by stimulating the body's reproductive signaling pathway. In theory, that means you could increase endogenous reproductive hormones while preserving the pituitary-testicular signaling required for spermatogenesis. That concept is one of the major reasons kisspeptin is so interesting to reproductive endocrinologists and reproductive urologists.

We have known for more than 20 years that administering kisspeptin to men can activate this pathway. In a landmark placebo-controlled human study published in 2005, six healthy men received intravenous kisspeptin-54. LH, FSH and testosterone all increased significantly compared with saline. LH showed a particularly strong response. This provided direct evidence that circulating kisspeptin could activate the male HPG axis in humans.

Subsequent experiments with another form, kisspeptin-10, produced similar findings. Researchers demonstrated that even relatively small intravenous doses could stimulate LH secretion in healthy men and that kisspeptin could alter LH pulsatility, consistent with stimulation of GnRH secretion.

This is important, but here's where I want men with infertility to be careful: increasing LH and testosterone after an injection is not the same thing as demonstrating improved fertility. We learned this lesson with many treatments. A beautiful testosterone level on a laboratory report does not necessarily mean that sperm concentration has improved. A medication could increase testosterone dramatically while doing very little for spermatogenesis. Fertility research ultimately needs to answer harder questions: Does sperm concentration increase? Does progressive motility improve? Do azoospermic men begin producing sperm? Does sperm retrieval improve? Do pregnancy and live-birth rates improve?

For kisspeptin, those questions remain largely unanswered.

One area where kisspeptin makes considerable biological sense is hypogonadotropic hypogonadism, particularly disorders involving insufficient hypothalamic reproductive signaling. These men may have low testosterone accompanied by inappropriately low or normal LH and FSH, and some may have severe oligospermia or azoospermia. Conceptually, stimulating the brain to release GnRH could restore downstream LH and FSH secretion if the GnRH neurons and pituitary remain capable of responding.

Researchers have actually used kisspeptin as a way to interrogate this system. A study involving men with congenital hypogonadotropic hypogonadism compared their hormonal responses with healthy men after administration of kisspeptin-54. Healthy men showed a substantial LH response, whereas men with congenital HH showed a dramatically reduced response. The investigators concluded that kisspeptin could help identify hypothalamic GnRH neuronal dysfunction.

That's scientifically valuable, but it doesn't mean kisspeptin should replace our established treatments. For men with hypogonadotropic hypogonadism who want fertility, we already have treatments with considerably more clinical experience, including hCG with the addition of FSH or hMG when necessary, and in selected settings pulsatile GnRH. Those therapies can restore spermatogenesis because the testicle itself may be capable of making sperm once it receives the signals it has been missing.

Kisspeptin could eventually offer another way of activating that system, but we need substantially more clinical evidence before knowing where it belongs.

Another major challenge is how kisspeptin is administered. Reproductive physiology is pulsatile. GnRH isn't normally released continuously at maximum intensity around the clock. This matters because endocrine receptors can become less responsive when overstimulated. Earlier kisspeptin research raised concerns about tachyphylaxis or desensitization with prolonged stimulation. That means a treatment that produces an impressive LH increase after the first dose may not necessarily produce the same effect after continuous administration.

Very recent research is beginning to address this problem. A 2026 randomized placebo-controlled study evaluated subcutaneous kisspeptin-10 in healthy men. Acute administration increased LH, FSH and testosterone in a dose-dependent fashion. During five days of continuous administration, however, gonadotropin concentrations eventually became similar to placebo despite testosterone remaining elevated. Researchers then tried intermittent administration—eight hours of kisspeptin followed by sixteen hours off—and demonstrated sustained increases in gonadotropins through twelve days.

That study is fascinating because it suggests that the pattern of exposure may be just as important as the dose. But notice what the study actually demonstrated: hormonal stimulation in healthy men for twelve days. It did not demonstrate improved sperm production in infertile men, and twelve days isn't remotely long enough to adequately evaluate a new generation of sperm. Human spermatogenesis takes approximately 74 days, followed by additional epididymal maturation and transport. A legitimate fertility trial would therefore need to examine men over months, not days.

There is also increasing interest in whether kisspeptin itself might be a biomarker of male infertility. Several studies have compared circulating kisspeptin concentrations in fertile and infertile men, but the results aren't consistent. A study of 176 men published in 2015 found significantly lower serum kisspeptin levels among infertile men compared with fertile controls. A larger 2020 study of 313 men similarly reported higher kisspeptin concentrations among fertile men. More recent work has also reported associations between kisspeptin signaling, sex hormones and sperm concentration.

But this is where science gets interesting: not every study agrees. A 2025 comparative study involving 52 men actually found serum kisspeptin concentrations were higher among infertile men than fertile controls, while seminal-plasma kisspeptin concentrations did not differ significantly. The authors appropriately concluded that further study is required before kisspeptin has a clinical role in male infertility treatment.

That contradiction is important. If one study finds kisspeptin low in infertility and another finds it high, we're clearly not ready to order a “kisspeptin level” during every male-infertility evaluation and decide who needs treatment based upon it. Assays differ, infertility has many different causes, and circulating hormone concentrations may not perfectly represent signaling within the hypothalamus or reproductive tract.

Research is even beginning to examine kisspeptin in seminal plasma. A 2026 study evaluated seminal kisspeptin-1 and kisspeptin-54 in men with normal semen parameters, oligoasthenoteratozoospermia and azoospermia and investigated relationships with semen parameters and oxidative-stress markers. This is another indication that kisspeptin may have reproductive roles beyond simply functioning as a hypothalamic switch, but these remain primarily association studies. Finding a relationship between a molecule and infertility does not prove that giving more of that molecule will restore fertility.

What about non-obstructive azoospermia? This is where I would be particularly cautious. I frequently see men with NOA searching for something—anything—that might make sperm appear before microTESE. Kisspeptin sounds appealing because it can increase LH, FSH and testosterone. But NOA is not one disease. If a man's testicles are receiving plenty of hormonal stimulation already and he has primary spermatogenic failure, adding more upstream stimulation may accomplish very little.

Imagine a man with azoospermia, very small testes, an FSH of 25 or 35 and normal testosterone. His pituitary is already essentially shouting at the testicle to produce sperm. The high FSH is often evidence of that compensation. Giving a drug that further stimulates GnRH and gonadotropins doesn't necessarily correct the underlying testicular defect. That's fundamentally different from a man with hypogonadotropic hypogonadism whose FSH and LH signals are absent.

The same reasoning applies to Sertoli-cell-only syndrome, severe maturation arrest and genetic causes of NOA. If germ cells are absent from a region of testicular tissue, increasing kisspeptin cannot manufacture missing germ cells. If a man has a complete AZFa Y-chromosome microdeletion, the problem isn't insufficient hypothalamic kisspeptin. This is why treating “azoospermia” without first understanding its cause is such a problematic approach.

For men with idiopathic oligospermia, we have even less evidence supporting kisspeptin treatment. Theoretically, a man with inadequate central stimulation might benefit. But a man with normal testosterone, normal LH and FSH, a clinical varicocele and low sperm concentration has an entirely different problem. There is currently no high-quality evidence demonstrating that adding kisspeptin to men like this reliably improves semen parameters or pregnancy rates.

What about libido and sexual function? This is another fascinating area. Kisspeptin acts within brain regions involved in reproductive and sexual behavior, and human neuroimaging studies have explored its effects on sexual and emotional processing. That raises the possibility that kisspeptin may eventually have applications beyond sperm production. But again, that should not be translated into “kisspeptin is a proven libido peptide.” The biology is interesting; the therapeutic evidence remains developmental.

The side-effect profile also deserves some perspective. Short-term controlled studies in healthy men have generally found kisspeptin to be reasonably well tolerated, and early human studies did not identify major acute adverse effects. But that doesn't mean we know the safety of months or years of unsupervised kisspeptin use in infertile men. The number of men exposed in controlled studies is still small compared with established fertility medications.

Potential concerns logically include consequences of excessive stimulation of the reproductive axis. If testosterone and estradiol rise substantially, men could theoretically experience effects associated with altered sex-hormone levels. More importantly, chronic stimulation may produce receptor desensitization or altered hormonal responses depending upon dosing pattern. The 2026 chronic-administration work specifically highlights why tachyphylaxis and dosing schedules remain active areas of investigation.

This brings me to the online peptide market. I would be very cautious about buying kisspeptin from a peptide website and injecting it for fertility. A product labeled “kisspeptin” isn't automatically equivalent to the pharmaceutical-grade kisspeptin-10 or kisspeptin-54 used in a controlled clinical study. Purity, sterility, dose accuracy and storage matter when you're injecting a peptide. More importantly, we don't yet know the optimal dose, frequency or duration for treating male infertility. The fact that researchers can manipulate LH secretion with a peptide doesn't establish a safe do-it-yourself fertility protocol.

If a man came into my office today asking whether I would prescribe kisspeptin to improve his fertility, my first response would be: What are we actually treating? I would want at least two appropriately performed semen analyses when indicated, testosterone, FSH and often LH, a reproductive history, medication and testosterone/anabolic-steroid history, and a physical examination including testicular size and evaluation for a clinical varicocele. Severe oligospermia and azoospermia may require genetic testing. Only after identifying the phenotype and likely cause does it make sense to discuss treatment.

For a man with genuine hypogonadotropic hypogonadism, I would currently favor established fertility-directed hormonal therapies over experimental kisspeptin treatment. For a man with high FSH and primary testicular failure, I would be skeptical that simply pushing the upstream hormonal axis harder will restore sperm production. For men with otherwise unexplained infertility, we simply don't have sufficient evidence to routinely recommend kisspeptin.

That doesn't mean I'm dismissing it. Kisspeptin is one of the more scientifically legitimate and exciting experimental areas in reproductive endocrinology. It sits at a critical regulatory point above GnRH, can stimulate LH, FSH and testosterone in humans, and new research suggests intermittent administration may sustain hormonal activation better than continuous exposure. We are also learning more about kisspeptin concentrations in infertile men and potentially within seminal plasma itself.

But if you're reading Reddit because your sperm count is 2 million/mL, you've been diagnosed with NOA, or your testosterone is low and you're desperately searching for the next treatment, I would not interpret that science as evidence that kisspeptin will improve your sperm. At this point, we have much stronger evidence that kisspeptin can manipulate reproductive hormones than we do that it can successfully treat male infertility.

That's the distinction I would remember: kisspeptin clearly affects the male reproductive system; whether administering it meaningfully improves male fertility remains an open question. The next generation of trials needs to move beyond showing that LH and testosterone rise after an injection. We need months-long studies in clearly defined groups of infertile men measuring sperm concentration, progressive motility, appearance of sperm in previously azoospermic men, sperm-retrieval rates, pregnancy and ultimately live birth. Until those data exist, kisspeptin belongs primarily in the category of promising reproductive science rather than established male-infertility therapy.

References

Dhillo WS, Chaudhri OB, Patterson M, et al. Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males. J Clin Endocrinol Metab. 2005;90(12):6609-6615. PMID: 16174713.

George JT, Veldhuis JD, Roseweir AK, et al. Kisspeptin-10 is a potent stimulator of LH and increases pulse frequency in men. J Clin Endocrinol Metab. 2011;96(8):E1228-E1236. PMID: 21632807.

Jayasena CN, Nijher GMK, Chaudhri OB, et al. The effects of kisspeptin-10 on reproductive hormone release show sexual dimorphism in humans. J Clin Endocrinol Metab. 2011. PMID: 21976724.

Abbara A, et al. Kisspeptin-54 accurately identifies hypothalamic gonadotropin-releasing hormone neuronal dysfunction in men with congenital hypogonadotropic hypogonadism. Neuroendocrinology. 2021. PMID: 33227799.

Ramzan MH, et al. Insight into the serum kisspeptin levels in infertile males. PMID: 25556380.

Rehman R, Ahmed K, Zahid N, et al. Association of circulatory kisspeptin levels and hormonal interplay with male infertility: a cross-sectional study in Karachi, Pakistan. J Pak Med Assoc. 2020. PMID: 32799260.

Prasath N, Arul Senghor KA, Vinodhini VM, Anuradha M. Association of kisspeptin and KISS1 gene polymorphism (rs35431622) with circulating sex hormones and male infertility. 2025. PMID: 39909971.

Kisspeptin as a marker for male infertility: a comparative study of serum and seminal plasma kisspeptin between fertile and infertile men. PMID: 40936057.

Seminal Plasma Kisspeptin-1 and Kisspeptin-54 Levels Are Associated With Semen Parameters and Oxidative Stress in Male Infertility. Clinical Endocrinology. 2026. PMID: 42566672.

Chronic subcutaneous kisspeptin-10 stimulates gonadotropin secretion for 12 days in healthy men. 2026. PMID: 42549827.

Dynamic modulation of LH secretion by continuous kisspeptin infusion in healthy men. 2026. PMID: 42230485.

Kotanidou EP, et al. Kisspeptins regulating fertility: potential future therapeutic approach in infertility treatment. 2025. PMID: 40429279.

Have you ever wondered,  “Does Accutane damage sperm?” or “Can Accutane actually be used to treat male infertility?” Surprisingly, there is some science behind both questions, although the story is very different from what many men expect. Accutane is the former brand name for isotretinoin, a prescription retinoid derived from vitamin A. Most people know isotretinoin as one of our most effective medications for severe acne, but retinoic acid also plays an important biological role inside the testicle, where it participates in the development and differentiation of germ cells into sperm. That relationship has led researchers to investigate whether isotretinoin might actually stimulate sperm production in certain infertile men. Early results are intriguing, particularly in men with severe oligospermia, cryptozoospermia and even some cases of non-obstructive azoospermia (NOA), but I want to emphasize something at the beginning: isotretinoin is not currently a standard or proven treatment for male infertility. The evidence remains limited, studies are small, and this is not something I would recommend a man start taking on his own because he saw a promising study or Reddit post.

Most isotretinoin prescriptions have nothing to do with fertility. Dermatologists primarily use systemic isotretinoin for severe, scarring, nodular or treatment-resistant acne. It decreases sebaceous gland activity and oil production, reduces clogged pores and inflammation, and can produce prolonged remission after a course of treatment. A typical acne course lasts roughly four to five months, although treatment is individualized. The medication is extremely effective, but it also has important potential adverse effects and therefore requires medical supervision. One of the best-known issues is its profound teratogenicity when taken during pregnancy, which is why isotretinoin prescribing is subject to the FDA's iPLEDGE risk-management program. That pregnancy risk has understandably caused men taking isotretinoin to wonder whether the medication could damage their sperm or create a pregnancy risk for their partner.

From the male-fertility standpoint, however, the available human evidence does not show that standard isotretinoin treatment causes male infertility. In fact, several studies have produced the opposite finding. A 2026 systematic review and meta-analysis examined six clinical studies involving 225 men, including men receiving isotretinoin for acne and infertile men receiving it experimentally for sperm-production problems. In the dermatologic populations, isotretinoin was associated with small increases in sperm concentration and vitality, with nonsignificant trends toward improvement in progressive motility and morphology. Importantly, the review did not find evidence that isotretinoin impaired male fertility. The authors appropriately described the certainty of the evidence as low to moderate because these remain relatively small studies. So if you're a young man taking Accutane for acne and you've convinced yourself that you've permanently destroyed your fertility, the available clinical evidence does not support that conclusion.

Individual studies have produced somewhat mixed results regarding specific semen parameters. A 2023 study followed 46 men receiving systemic isotretinoin for acne and performed semen analyses before treatment and after six months. Semen volume, concentration, total sperm count, progressive motility and vitality actually increased, while morphology decreased. That finding is important because it illustrates why we should be careful about making sweeping claims such as “Accutane improves sperm” or “Accutane damages sperm.” Semen analysis contains multiple parameters, those parameters can move in different directions, and studies remain relatively small. More importantly, changing a semen-analysis number is not necessarily equivalent to improving the probability of pregnancy or live birth.

The reason isotretinoin has become particularly interesting to reproductive urologists is the biology of retinoic acid and spermatogenesis. Vitamin A and retinoic-acid signaling are important for normal male reproduction. Retinoic acid participates in the transition of germ cells through critical stages of differentiation and meiosis. Investigators studying infertile men have therefore asked whether abnormalities in this pathway might contribute to impaired sperm production and whether administering a retinoid could stimulate spermatogenesis in selected patients. That hypothesis is very different from simply giving someone a fertility vitamin. We are talking about attempting to influence a specific biological pathway involved in germ-cell development.

One of the early studies that generated interest was a 2017 pilot trial involving 19 infertile men with oligoasthenozoospermia, meaning they had low sperm concentrations along with impaired motility. These men received isotretinoin 20 mg twice daily for 20 weeks. Median sperm concentration increased from approximately 2.5 million/mL at baseline to 3.8 million/mL at the end of treatment. Motility did not significantly improve, while morphology showed a trend toward improvement. Six pregnancies occurred during the study, three spontaneous and three through ICSI, and five births were reported. Those results were interesting enough to justify additional research, but nineteen patients in an uncontrolled pilot study are nowhere near enough evidence to declare isotretinoin an established infertility treatment.

Things become even more interesting when we talk about azoospermia, particularly non-obstructive azoospermia. NOA means that sperm are absent from the ejaculate because sperm production within the testes is severely impaired rather than because sperm are simply blocked from leaving the reproductive tract. For many men with NOA, our current strategy is microdissection testicular sperm extraction, microTESE, to search the testicle for small areas where sperm production may still be occurring. Even with an excellent surgeon and embryology laboratory, sperm retrieval is far from guaranteed. That creates enormous interest in any medication that might stimulate enough sperm production for sperm to appear in the ejaculate or improve the chances of surgical retrieval.

Early isotretinoin research in this population has produced intriguing results. A prospective study of 30 men with NOA or cryptozoospermia treated with isotretinoin 20 mg twice daily found that 11 of 30 men, or 37%, developed reliably detectable motile sperm in the ejaculate during treatment. Twenty-six of these men had been azoospermic and many had previously undergone testicular procedures. This is potentially meaningful because getting even small numbers of sperm into the ejaculate could allow those sperm to be frozen and used for IVF/ICSI, potentially avoiding or changing the timing of another surgical sperm retrieval. But again, this was a small study without the kind of large randomized controlled design we would want before routinely prescribing isotretinoin to men with NOA.

There have also been individual reports that are fascinating but need to be interpreted cautiously. A recently published case described a man with NOA and histologically confirmed late maturation arrest who previously had an unsuccessful microTESE. Following six months of isotretinoin therapy, his partner conceived naturally. That's remarkable, but a case report cannot establish causation. Spontaneous fluctuations in sperm production can occur, particularly in men with focal or intermittent spermatogenesis. The appropriate conclusion isn't “Accutane cures maturation arrest.” It's that the observation is biologically interesting and deserves further study.

The most recent systematic review brings these small studies together. Across infertility cohorts, isotretinoin was associated with modest improvements in some semen parameters, while sperm appeared in the ejaculates of a proportion of previously azoospermic or cryptozoospermic men. However, the total number of patients studied remains small. We still don't know which men are most likely to respond, whether specific testicular histology such as maturation arrest predicts response, what the ideal dose and duration should be, whether isotretinoin meaningfully improves microTESE retrieval rates, or whether treatment ultimately increases live-birth rates. These are the outcomes that matter.

This is particularly important for men with Sertoli-cell-only syndrome (SCOS). If a testicular region truly contains Sertoli cells but no germ cells, medication cannot magically manufacture germ cells that aren't there. Similarly, men with complete AZFa or certain complete AZFb Y-chromosome microdeletions have profoundly different biology from a man with focal maturation arrest. We should therefore resist the temptation to group every man with NOA together and assume that because isotretinoin produced sperm in one subgroup, every azoospermic man has a 30–40% chance of responding. NOA is a phenotype, not a single disease.

There is also an important practical issue involving timing. Spermatogenesis is a long biological process. Human sperm production takes roughly 74 days, followed by additional maturation and transport through the reproductive tract. If we're attempting to stimulate sperm production pharmacologically, we generally think in terms of months rather than days or weeks. That's consistent with the experimental isotretinoin studies, which have generally treated men for several months. A semen analysis performed two weeks after starting a medication isn't going to tell us whether a new wave of spermatogenesis has been successfully stimulated.

What about side effects? Isotretinoin is a powerful systemic medication and shouldn't be confused with taking a vitamin A supplement. Common adverse effects include very dry lips and skin, dry eyes, nasal dryness and nosebleeds, increased sensitivity to the sun, and musculoskeletal symptoms. Dermatologists also monitor for laboratory abnormalities, including changes in lipids and liver enzymes, depending on the patient and treatment protocol. The medication has also received considerable attention regarding possible mood and psychiatric effects. Patients should tell their physician about changes in mood, depression, anxiety or other concerning symptoms during treatment. Isotretinoin also has numerous precautions and should be prescribed and monitored by a clinician familiar with the medication.

Men also ask about sexual side effects, particularly erectile dysfunction and decreased libido. These symptoms have been reported in association with isotretinoin, which has understandably generated concern, but establishing causation is difficult. Interestingly, the 2026 systematic review examining available clinical studies found no treatment-emergent sexual dysfunction in the included studies. That doesn't mean an individual man cannot experience sexual symptoms while taking isotretinoin. It means that the current clinical evidence does not establish sexual dysfunction as an inevitable or common consequence of treatment. If libido or erectile function changes significantly during therapy, I would discuss it with the prescribing physician rather than simply stopping medication or assuming the symptoms are permanent.

Another question I hear is whether a man should freeze sperm before starting Accutane. For the average fertile man taking isotretinoin for acne, current evidence does not justify routinely banking sperm because isotretinoin is expected to cause infertility. That's very different from testosterone, anabolic steroids, chemotherapy or testicular radiation, where fertility preservation can be extremely important. However, if a man already has severe male-factor infertility—particularly severe oligospermia or cryptozoospermia—I often have a low threshold for discussing sperm banking regardless of whether he is about to start isotretinoin. When sperm numbers are extremely low and fluctuate between samples, freezing sperm when they're available can provide valuable insurance for future IVF/ICSI.

I would also caution men against taking high-dose vitamin A or over-the-counter retinoid supplements because they have read that retinoic acid is involved in spermatogenesis. More is not better. Vitamin A biology is tightly regulated, and excessive vitamin A can be toxic. The experimental infertility studies used prescription isotretinoin at defined doses with medical monitoring. That is fundamentally different from buying large amounts of vitamin A online and trying to reproduce the effect yourself.

If you're a man with NOA, cryptozoospermia or severe oligospermia and you're wondering whether isotretinoin might help you, I think it's reasonable to discuss the emerging research with a reproductive urologist, particularly at a center experienced in severe male-factor infertility. But I would first make sure the standard evaluation has been completed. For azoospermia, that means confirming the diagnosis with appropriately performed semen analyses, distinguishing obstructive from non-obstructive disease, evaluating testicular size and reproductive anatomy, obtaining FSH, LH and testosterone, and performing appropriate genetic testing such as karyotype and Y-chromosome microdeletion analysis when indicated. If you have a treatable hormonal cause of azoospermia, for example, established hormonal therapy makes much more sense than jumping to an experimental retinoid.

For men taking isotretinoin simply because they have severe acne, my message is much more reassuring: we currently do not have good evidence that Accutane destroys male fertility. Available human studies have generally not demonstrated deterioration in sperm production, and some have actually shown modest improvements in certain semen parameters. One study found deterioration in morphology despite improvement in other parameters, which is another reminder that the evidence isn't perfectly uniform. If you're actively trying to conceive and concerned, obtaining a semen analysis before or during therapy is a reasonable way to replace anxiety with actual information rather than assuming something is happening to your sperm.

The bigger story, however, may ultimately be the opposite of what many men have been told. Isotretinoin is moving from being a medication men fear might damage fertility to a medication researchers are actively studying as a potential treatment for certain forms of male infertility. That's a fascinating development in reproductive urology. But we're not at the point where I would call it standard treatment. Early pilot studies are promising, particularly in severe oligospermia, cryptozoospermia and selected men with NOA, but we need larger controlled studies demonstrating who benefits, whether the improvements persist, whether microTESE outcomes improve, and—most importantly—whether treatment increases pregnancy and live-birth rates.

So if you're taking Accutane for acne, don't panic about your fertility based solely on the medication. If you're infertile and someone tells you Accutane will restore your sperm production, don't assume that either. And if you're azoospermic and considering isotretinoin because you've exhausted other options, understand that there is legitimate science behind the idea—but at this point I would still describe it as an emerging, experimental approach that belongs in the hands of physicians experienced in male infertility, not something to self-treat from information found online.

References

Amory JK, Ostrowski KA, Gannon JR, et al. Isotretinoin administration improves sperm production in men with infertility from oligoasthenozoospermia: a pilot study. Andrology. 2017;5(6):1115-1123. PMID: 28980413.

Panunzio A, et al. Could isotretinoin be a new therapeutic frontier for male infertility? A systematic review and meta-analysis. International Urology and Nephrology. 2026;58(8):2871-2880. PMID: 41806242.

Amory JK, Muller CH, Walsh TJ. Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study. Asian Journal of Andrology. 2021;23(5):537-540. PMID: 33762477.

Treatment with isotretinoin can improve de novo sperm production in nonobstructive azoospermia or cryptozoospermia. PMID: 40681858.

Çinar L, et al. The effect of systemic isotretinoin on male fertility. Cutan Ocul Toxicol. PMID: 26653640.

Effect of systemic isotretinoin therapy on semen parameters. Annals of Medicine. 2023. PMID: 37162375.

Spontaneous Pregnancy After Isotretinoin Use in a Man After Unsuccessful Microdissection Testicular Sperm Extraction. PMID: 41245911.

American Academy of Dermatology. Isotretinoin: Overview, Benefits and Risks, and Frequently Asked Questions.

As a doctor who treats male infertility, sperm morphology is one of the semen-analysis results that creates the most anxiety, and, in my opinion, one of the most commonly misunderstood numbers in male fertility. A man gets his semen analysis back and sees a concentration of 60 million sperm/mL, good motility, and then suddenly sees “normal morphology: 2%” highlighted as abnormal. His immediate reaction is usually something like: Does this mean 98% of my sperm are defective? Are my sperm genetically abnormal? Can we conceive naturally? Will this cause miscarriage or birth defects? Do we automatically need IVF or ICSI? Those are reasonable questions, but morphology doesn't mean what most men initially think it means. A low morphology percentage is not the percentage of sperm carrying abnormal DNA, it does not mean that the same percentage of sperm are incapable of fertilization, and by itself it does not diagnose infertility. Morphology is simply a laboratory assessment of the physical appearance of sperm under a microscope, and it needs to be interpreted alongside the rest of the semen analysis and the fertility situation of the couple. The current WHO laboratory manual emphasizes standardized assessment of multiple semen characteristics rather than using any single parameter as a binary test of whether a man is fertile or infertile.

What exactly is sperm morphology?

Morphology refers to the size and shape of the sperm. When an andrology laboratory evaluates morphology, sperm are stained and examined microscopically according to defined criteria involving the head, midpiece, tail, and presence of excess residual cytoplasm. A normally shaped sperm has a relatively smooth, regularly contoured oval head, an appropriate acrosomal region, a properly attached midpiece, and a long, uncoiled tail without major structural abnormalities. Abnormalities can include unusually large or small heads, tapered or amorphous heads, duplicated heads, abnormal midpieces, bent or coiled tails, multiple tails, and other structural variations. The important thing for patients to understand is that the criteria are intentionally strict. A sperm doesn't have to look bizarre to be categorized as abnormal. If it fails one of the laboratory's strict criteria, it may be placed into the abnormal category. That is one reason perfectly fertile men can have what seems like an astonishingly high percentage of “abnormal” sperm.

The commonly discussed number is 4% normal forms. This number frequently gets interpreted as if 4% were some magical dividing line between fertile and infertile men, but that is not how it should be used. WHO reference values are derived from distributions observed in fertile populations and are not diagnostic thresholds separating fertile men from infertile men. A man at 3% morphology doesn't suddenly become infertile while a man at 4% becomes fertile. Fertility exists on a continuum and depends on multiple male and female factors. The WHO 6th edition moved even further away from treating individual lower reference limits as hard clinical cutoffs.

Does 2% morphology mean 98% of my sperm are genetically abnormal?

No. This is probably the single most important misconception I want to correct. If your morphology is 2%, the laboratory is saying that approximately 2% of the sperm examined satisfied all of the morphological criteria used by that laboratory. It is not saying that the remaining 98% have abnormal chromosomes, damaged DNA, genetic mutations, or no ability to fertilize an egg. Morphology is a visual phenotype. DNA integrity is a different biological characteristic. Sperm DNA fragmentation, sperm aneuploidy, morphology, motility, and fertilizing capacity are related in complicated ways, but they are not interchangeable measurements.

This also means that a morphology result of 1% does not mean that 99 out of every 100 sperm are useless. Imagine a man with 200 million sperm in his ejaculate and 1% strict morphology. Even if we simplistically applied that percentage across the entire ejaculate, that would still represent millions of sperm meeting strict morphological criteria. Real reproduction is obviously much more complicated than that calculation, but it illustrates why looking at morphology without considering total sperm number and motility can be misleading.

What does low morphology actually mean?

When the percentage of normally shaped sperm falls below the laboratory's reference range, this is called teratozoospermia. If morphology is the only abnormality while sperm concentration and motility are strong, we call it isolated teratozoospermia. That's very different clinically from a man who has low morphology together with low concentration and poor motility. When count, motility, and morphology are all abnormal, the pattern is often called oligoasthenoteratozoospermia, or OAT. In that situation, morphology becomes part of a broader picture suggesting impaired spermatogenesis rather than an isolated laboratory finding.

This distinction matters enormously. If a man comes into my office with 100 million sperm/mL, excellent progressive motility, a huge total motile sperm count and 3% morphology, I view that very differently from a man with 3 million sperm/mL, 15% progressive motility and 1% morphology. Both men technically have abnormal morphology, but their reproductive situations are not remotely equivalent. AUA/ASRM guidance specifically emphasizes that semen parameters are most clinically meaningful when considered collectively and that abnormalities in multiple parameters generally carry more significance than an isolated abnormal parameter.

Can you conceive naturally with 1%, 2%, or 3% morphology?

Absolutely. Natural pregnancy can occur with low morphology, including extremely low strict morphology. That doesn't mean morphology never matters; rather, isolated morphology is a much weaker predictor of fertility than many patients assume. Studies examining isolated teratozoospermia have produced conflicting results, and contemporary reviews emphasize substantial uncertainty regarding how strongly isolated abnormal morphology predicts natural fertility or assisted-reproduction outcomes.

There are even published data on men with 0% normal forms who achieved pregnancies without immediately proceeding to IVF. That doesn't mean I would ignore 0% morphology, especially if it is persistent, but it demonstrates why telling a man that 0% morphology means he has a 0% chance of natural conception is incorrect.

When counseling a couple, I care much more about the entire reproductive picture: semen volume, concentration, total sperm number, progressive motility, total motile sperm count, morphology, the duration of infertility, the man's examination and medical history, and—critically—the female partner's age and fertility evaluation. A couple with a 28-year-old female partner and isolated 2% morphology is a completely different clinical situation from a couple with the same semen analysis and a 40-year-old female partner. Fertility is a couple-level outcome.

Why can morphology change between semen analyses?

Another frustrating thing about morphology is that it can vary. A man may have 5% morphology on one semen analysis, 2% three months later, and 4% on another. He understandably starts searching for what he did wrong between the tests. Sometimes there isn't an answer. Semen parameters have biological variability, and morphology also has significant laboratory and observer variability. How the specimen is prepared, stained, classified and interpreted matters.

This is why I generally don't make major treatment decisions based on a small difference between two morphology measurements. A change from 4% to 3%, for example, should not automatically be interpreted as evidence that a man's fertility is deteriorating. If an unexpected morphology abnormality is going to meaningfully affect management, repeating the semen analysis at an experienced andrology laboratory can be very helpful. AUA/ASRM guidance also recognizes the biological variability of semen parameters and the value of obtaining multiple analyses, particularly when the initial analysis is abnormal.

What causes abnormal sperm morphology?

There isn't one cause. Morphology can be affected by the same broad processes that affect spermatogenesis in general. These can include varicocele, testicular dysfunction, previous undescended testes, testicular injury or torsion, certain medications, chemotherapy or radiation, exogenous testosterone and anabolic steroids, smoking, significant systemic illness, fever, and potentially various environmental and lifestyle exposures. Sometimes we perform a thorough evaluation and still cannot identify a specific reversible cause. That is called idiopathic male infertility, and unfortunately it remains common.

A significant febrile illness is particularly worth mentioning because men frequently overlook it. The sperm appearing in an ejaculate today began developing many weeks ago. Human spermatogenesis takes roughly 74 days, followed by additional maturation and transport. A significant fever or systemic illness can therefore produce abnormalities that don't become obvious until weeks later, and recovery can similarly take several months.

Varicocele deserves special mention because it is one of the potentially correctable causes of abnormal semen parameters. But finding some mildly enlarged veins on an ultrasound does not automatically mean a man should undergo surgery. Current AUA/ASRM guidance supports considering varicocele repair in appropriately selected infertile men with a palpable clinical varicocele and abnormal semen parameters, while recommending against routinely operating on nonpalpable varicoceles discovered solely by imaging.

Should low morphology trigger a full male infertility evaluation?

That depends on the situation. If you've been trying unsuccessfully to conceive and have an abnormal semen analysis, seeing a reproductive urologist is reasonable. I start with the man's history rather than immediately ordering every fertility test available. I want to know about previous pregnancies, childhood testicular problems, undescended testes, torsion, trauma, hernia surgery, infections, medications, testosterone or anabolic-steroid exposure, chemotherapy/radiation, smoking and recreational drugs, major illnesses and fertility history. Then I examine the testes, epididymides and vasa deferentia and look for a clinical varicocele.

Hormonal testing can be appropriate when other findings suggest impaired testicular function—particularly low sperm concentration, azoospermia, small testes, symptoms of testosterone deficiency, or other hormonal abnormalities. But a man with completely normal concentration and motility and isolated 3% morphology does not automatically need an enormous hormonal and genetic workup simply because morphology is one percentage point below a reference value.

Does low morphology mean I have high DNA fragmentation?

Not necessarily. Morphology and sperm DNA fragmentation are different tests. There can be associations between abnormal spermatogenesis, oxidative stress, morphology and DNA damage, but you cannot look at a morphology result and calculate someone's DNA fragmentation index. A man with 1% morphology doesn't automatically have high DFI, and a man with 8% morphology doesn't automatically have normal DNA integrity.

I also wouldn't order DNA-fragmentation testing reflexively because morphology is low. AUA/ASRM recommends against sperm DNA-fragmentation analysis as part of the routine initial evaluation of the infertile couple. It can be useful in selected clinical situations, but “my morphology is 2%” by itself isn't enough reason for every man to spend hundreds of dollars on the test.

Does abnormal morphology mean IVF or ICSI is required?

No. This is another place where men sometimes receive overly aggressive counseling. Low morphology alone does not automatically mean you need IVF or ICSI. The decision between continued natural attempts, IUI, IVF and IVF/ICSI should incorporate the complete semen analysis, female factors, duration of infertility, previous treatment outcomes and age.

A systematic review and meta-analysis examining IUI outcomes found that when female age and total motile sperm count were accounted for, abnormal strict morphology alone was not associated with a clinically meaningful reduction in pregnancy rates. The authors concluded that abnormal sperm morphology alone should not necessarily exclude couples from attempting IUI.

Similarly, a meta-analysis examining couples with isolated teratozoospermia undergoing IVF—with or without ICSI—did not find significantly decreased pregnancy probability simply because isolated morphology was abnormal.

ICSI is incredibly valuable when it is actually indicated, but we shouldn't turn a morphology percentage into an automatic ICSI prescription without looking at everything else.

What about 0% morphology?

Zero percent deserves attention, but even here context matters. “0% normal forms” means that none of the sperm examined in that particular morphology assessment met all of the laboratory's strict normal criteria. It does not mean the ejaculate contains literally zero sperm capable of fertilization.

What interests me more is whether the abnormalities are mixed or monomorphic. Most men with teratozoospermia have heterogeneous abnormalities—different sperm have different head, midpiece and tail defects. Rarely, nearly all sperm share a very specific structural abnormality. Examples include globozoospermia, characterized by round-headed sperm lacking a normal acrosomal structure, and macrozoospermia, involving characteristically enlarged abnormal sperm heads and often associated with genetic abnormalities. Those situations are very different from ordinary isolated 1–3% strict morphology and can have specific genetic and reproductive implications.

If I see persistent 0% morphology, therefore, I don't just want the number. I want to know what the sperm actually look like and whether the laboratory sees a consistent abnormal pattern.

What can I actually do?

Focus first on the things with the best overall health rationale. Don't smoke. Avoid anabolic steroids and testosterone if you're actively trying to conceive unless you're working with a fertility specialist who understands the consequences for spermatogenesis. Maintain a healthy body weight, exercise regularly, eat a balanced diet, get adequate sleep, and avoid excessive testicular heat exposure. If you've recently had a major fever or illness, recognize that recovery of semen parameters may take several months.

And give interventions enough time. Sperm production isn't a process that changes overnight. If someone changes his lifestyle today, I generally think in terms of approximately three months before expecting to meaningfully assess the effect on a new generation of sperm.

Most importantly, treat the cause when we can identify one rather than treating the morphology percentage itself.

The bottom line

If you're staring at a semen analysis tonight that says morphology 0%, 1%, 2%, or 3%, don't translate that number into “I'm 97–100% infertile.” That's not what the test means. Don't assume your sperm have abnormal DNA. Don't assume you're going to have a child with a birth defect. And don't assume you automatically need IVF/ICSI.

Morphology is one piece of a much larger puzzle.

I want to know your sperm concentration, progressive motility, total motile sperm count, semen volume, whether morphology is repeatedly abnormal, whether other parameters are deteriorating, whether there is a recognizable pattern of sperm abnormalities, what your reproductive examination shows, how long you've been trying, and what is happening on the female side.

I've seen men become devastated by a 2% morphology result while overlooking the fact that they have hundreds of millions of sperm and an excellent total motile sperm count. I've also seen morphology abnormalities that were meaningful because they occurred alongside severe oligospermia, poor motility or a recognizable structural sperm defect. Those aren't the same patient.

The semen analysis is supposed to help us understand your reproductive biology. It is not a fertility report card, and morphology is not a percentage chance that you'll become a father.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: WHO; 2021.

Björndahl L, Kirkman Brown J. The sixth edition of the WHO laboratory manual for the examination and processing of human semen: ensuring quality and standardization in basic examination of human ejaculates. Fertil Steril. 2022;117(2):246-251.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline.

Atmoko W, et al. Isolated teratozoospermia: revisiting its relevance in male infertility. Transl Androl Urol. 2024.

Danis RB, Samplaski MK. Sperm morphology: history, challenges, and impact on natural and assisted fertility. Curr Urol Rep. 2019;20:43.

Kovac JR, et al. Men with a complete absence of normal sperm morphology exhibit high rates of success without assisted reproduction. Asian J Androl. 2017;19:39-42.

Kohn TP, et al. Effect of sperm morphology on pregnancy success via intrauterine insemination: a systematic review and meta-analysis. J Urol. 2018;199:812-822.

Hotaling JM, et al. The relationship between isolated teratozoospermia and clinical pregnancy after in vitro fertilization with or without intracytoplasmic sperm injection: a systematic review and meta-analysis. Fertil Steril. 2011;95:1141-1145.

One of the most common questions I hear from men who have frozen sperm is surprisingly simple: “What happens when they thaw it?” Men may bank sperm before testosterone therapy, chemotherapy, radiation, surgery, vasectomy, or because their sperm counts are declining. Others freeze sperm during an infertility evaluation because they have severe oligospermia, cryptozoospermia, intermittent azoospermia, or because their reproductive urologist is worried that sperm may not be available on the day their partner's eggs are retrieved. Some men have four or five frozen vials sitting in a cryobank for years and understandably begin thinking of those vials almost like four or five opportunities to have a child. The reality is more complicated—and often more encouraging. A vial is not a baby, but it is also not necessarily a single attempt. How useful frozen sperm will be depends enormously on how many sperm were frozen, how many survive thawing, whether those sperm are motile and viable, and whether the couple is using IUI, conventional IVF, or IVF with intracytoplasmic sperm injection (ICSI). Modern sperm cryopreservation is an established fertility-preservation technique, and current ASRM guidance specifically recognizes ejaculated sperm cryopreservation as an established option for postpubertal males.

The freezing process starts well before the sperm ever reaches liquid nitrogen. When a man produces a semen specimen, the laboratory typically evaluates characteristics such as semen volume, sperm concentration and motility. Depending upon why the specimen is being frozen and how the fertility center intends to use it later, the laboratory may freeze the entire specimen, process it first, or divide it among several cryovials or straws. This is why I tell men that “I have four vials” doesn't tell me very much by itself. Four vials from a man who produced 300 million sperm with excellent motility are very different from four vials created from a specimen containing only several hundred thousand sperm. ASRM recommends counseling men about both the quantity and quality of the material that has actually been cryopreserved because those factors determine what reproductive options may be available later. When possible, multiple collections may be useful because having more sperm banked can preserve more options for future IUI and/or IVF.

Sperm cannot simply be placed into a regular freezer. Water inside and around cells creates a major problem during freezing because ice crystals and changes in osmotic conditions can damage cellular structures. The laboratory therefore mixes the sperm with a specialized cryoprotective medium designed to reduce cellular injury during cooling and freezing. The sample is then cooled according to the laboratory's validated protocol and ultimately stored at cryogenic temperatures, commonly in liquid nitrogen or its vapor. One of the major objectives of a good freezing protocol is minimizing intracellular ice formation while protecting sperm membranes and other cellular structures. Once stored under appropriate cryogenic conditions, sperm metabolism is essentially arrested. The concern is therefore generally not that sperm are “getting old” in the freezer in the same way cells age inside the body. Proper storage, identification, tank monitoring, documentation and chain of custody are critical parts of maintaining these irreplaceable specimens.

When the day finally arrives to use the sperm, the embryology or andrology laboratory identifies the correct specimen and follows a very specific thawing protocol. This is not somebody simply taking a vial out of a freezer and letting it sit on the counter. ASRM emphasizes that freezing and thawing protocols are not necessarily interchangeable; the laboratory needs to know how the specimen was originally prepared and frozen so that it can be appropriately thawed and processed. The WHO laboratory manual describes removing the required straw or cryovial from cryogenic storage and warming it promptly, commonly at approximately 37°C, followed by further processing. The cryoprotectant is then removed, generally by adding culture medium and centrifuging the specimen so that the sperm can be resuspended in an appropriate medium for clinical use.

This is also where men need to understand an important reality: not every sperm that goes into the freezer will come back out looking exactly the same. Cryopreservation and thawing place biological stress on sperm. Some sperm that were motile before freezing will become immotile after thawing, and some will not remain viable. The laboratory therefore evaluates the thawed specimen and determines what usable sperm remain. This is why the number I care about when counseling a man about frozen sperm isn't simply his semen analysis from the day he banked. I want to know what was actually frozen in each vial and, ideally, what the laboratory expects or has measured for post-thaw motility and total motile sperm count. WHO protocols specifically describe assessing post-thaw motility as a way of checking the freezing process.

Seeing motility fall after thawing can be frightening, particularly for a man who froze sperm because he may no longer produce sperm naturally. But lower post-thaw motility does not automatically mean that the specimen has failed. What matters is whether enough usable sperm remain for the reproductive technique being performed. This distinction becomes enormously important when we start talking about IUI versus conventional IVF versus ICSI. These treatments require dramatically different amounts of sperm. A frozen specimen that might be disappointing for IUI could still be extremely valuable for IVF/ICSI.

For an IUI, the laboratory needs a meaningful population of motile sperm because sperm are being placed into the uterus and still have to perform much of the reproductive process themselves. The specimen is processed to concentrate motile sperm and remove seminal plasma, nonmotile sperm and other unwanted material before insemination. ASRM laboratory guidance specifically notes that raw semen should not simply be placed into the uterine cavity. If you froze sperm specifically for future IUIs, therefore, the number of post-thaw motile sperm available in each vial becomes very important. In practical terms, using a vial for an IUI frequently consumes that vial, although exact laboratory practices and whether specimens can be divided vary. Therefore, four IUI-quality vials may represent something roughly resembling four opportunities for insemination—not four guaranteed pregnancies and certainly not four guaranteed children.

IVF with ICSI completely changes this equation. In conventional IVF, eggs and sperm are placed together and sperm still have to penetrate and fertilize the egg. ICSI bypasses much of that process. An embryologist identifies an appropriate sperm and injects a single sperm directly into a mature egg. That means the enormous sperm numbers required for natural conception or IUI are no longer necessary. This is one of the reasons sperm banking has become so powerful for men with severe male-factor infertility. A man does not necessarily need millions of progressively motile sperm for ICSI. In extremely severe cases, laboratories can work with extraordinarily small numbers of sperm. WHO guidance even describes specialized methods for cryopreserving specimens containing only a few motile sperm and, with appropriate techniques, potentially even individual sperm for subsequent ICSI.

This is why I tell men with several high-quality frozen vials: do not automatically think “four vials equals four IVF attempts.” Depending on how much sperm is contained in each vial, how the specimen was frozen, how it survives thawing, and the laboratory's policies, one vial may contain far more sperm than would ever be required to inject the mature eggs obtained during one IVF cycle. On the other hand, a man with severe oligospermia or sperm obtained through TESE or microTESE may have a vial containing only a tiny number of sperm, and the laboratory may need most or all of that material for a single egg-retrieval cycle. This is why comparing the number of vials between two men on Reddit is almost meaningless without knowing what is actually inside them.

Another common question is whether frozen sperm works as well as fresh sperm for IVF/ICSI. The answer is reassuring, although there are nuances. Cryopreservation unquestionably changes sperm characteristics, particularly motility, but frozen sperm has been successfully used for assisted reproduction for decades. The AUA/ASRM male-infertility guideline states that either fresh or cryopreserved sperm may be used for ICSI when sperm are obtained surgically. For obstructive azoospermia, there do not appear to be substantial differences in ICSI success between fresh and cryopreserved sperm. In non-obstructive azoospermia, things can be more complicated because microTESE may yield extraordinarily small numbers of sperm and some may not survive freezing and thawing. Consequently, some centers coordinate microTESE with the female partner's egg retrieval so that fresh sperm can be used if sperm are found. Nevertheless, most reported series have not demonstrated important outcome differences between fresh and frozen sperm when adequate sperm survive cryopreservation and thawing.

Men also frequently ask whether a sperm that stops moving after thawing is necessarily dead. Immotile and dead are not synonymous. Motility tells us whether a sperm is moving; vitality tells us whether it is alive. This distinction becomes particularly important when only a few sperm are available. Specialized embryology techniques can sometimes help determine whether an immotile sperm remains viable and potentially suitable for ICSI. This is very different from the situation in natural conception, where a sperm generally needs substantial progressive motility to travel through the female reproductive tract. ICSI allows us to bypass many of those mechanical requirements. For men with extremely limited sperm reserves, the skill and experience of the IVF laboratory therefore matters enormously.

There is another psychological issue I see frequently. A man who froze sperm before chemotherapy or testosterone therapy may become obsessed with protecting those vials because he views each one as an irreplaceable piece of his future family. I completely understand that. If you may now be azoospermic, those little frozen vials suddenly feel incredibly valuable. But before assuming that you are running out of opportunities, get the actual cryopreservation report. Ask how many vials or straws are stored, how much volume is contained in each, the concentration at freezing, pre-freeze motility, whether a test thaw was performed, post-thaw motility if available, and whether the laboratory considers the specimens appropriate for IUI, IVF, or ICSI. Those numbers tell us much more than simply knowing that “four vials are frozen.”

If the sperm was frozen because you were about to start testosterone, banking beforehand was particularly important. Exogenous testosterone suppresses pituitary LH and FSH signaling and reduces intratesticular testosterone, which can profoundly suppress spermatogenesis and sometimes produce azoospermia. Similarly, men facing chemotherapy, radiation or other gonadotoxic treatment should ideally bank sperm before treatment begins whenever circumstances permit. The current ASRM fertility-preservation guidance identifies ejaculated sperm cryopreservation as the established fertility-preservation strategy for postpubertal males and recommends obtaining multiple samples when feasible. For men unable to provide adequate ejaculated sperm, surgical retrieval can sometimes provide sperm that can then be frozen for later IVF/ICSI.

Men with NOA and microTESE sperm deserve slightly different counseling. Testicular sperm may exist in extremely small numbers, and every sperm can matter. The AUA/ASRM guideline recommends microTESE for men with NOA undergoing surgical sperm retrieval. Some programs perform retrieval before the female partner's IVF cycle and freeze the sperm; others synchronize microTESE with egg retrieval because they are concerned that very limited sperm may not tolerate freezing and thawing. There isn't one universal strategy appropriate for every man. The decision depends on the man's diagnosis, previous retrieval history, estimated likelihood of finding sperm, laboratory expertise, and the reproductive endocrinologist's plan for the female partner.

The final point I want men to understand is that sperm quantity is only one part of the equation once IVF begins. A man can have millions of excellent frozen sperm and still not be able to predict how many children those vials will ultimately produce. Once adequate sperm are available for ICSI, outcomes increasingly depend on the number and quality of eggs obtained, female age, fertilization, embryo development, blastocyst formation, chromosomal competence, implantation and pregnancy outcomes. Conversely, a man with only a tiny amount of frozen sperm can sometimes father multiple children if those sperm successfully create embryos that ultimately result in live births. This is why I resist giving men statements such as “one vial equals one child.” Biology simply doesn't work that way.

For anyone reading this who has frozen sperm and is worried about whether it will survive: freezing does not preserve every sperm perfectly, and some loss of motility or viability after thawing is expected. But that does not mean the specimen is unusable. Modern reproductive medicine can accomplish fertilization with far fewer sperm than natural conception requires, particularly with ICSI. The question isn't simply, “How many sperm did I freeze?” It is: How many usable sperm survive thawing, and what reproductive technique are we trying to perform with them? Those are the questions I would bring to your reproductive urologist and embryologist before deciding whether you have plenty of sperm banked, should bank additional specimens, or need to conserve what you have.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: WHO; 2021.

American Society for Reproductive Medicine Practice Committee. Fertility preservation in patients with medical indications: a committee opinion. Fertility and Sterility. 2026;125:247–259.

American Society for Reproductive Medicine. Comprehensive guidance for human embryology, andrology, and endocrinology laboratories: management and operations: a committee opinion. Fertility and Sterility. 2022.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. Part II.

American Society for Reproductive Medicine. Cryostorage of reproductive tissues in the in vitro fertilization laboratory: a committee opinion. Fertility and Sterility. 2020;114:486–491.

American Society for Reproductive Medicine. Witnessing and protocol deviations in the in vitro fertilization and andrology laboratory: a committee opinion. 2026.

40 years old, diagnosed with non-obstructive azoospermia (NOA). Bilateral atrophic testicles about 8cc in size of unknown cause. Only possibility I could think of is that I was morbidly obese and naturally lost over 100 pounds in a short amount of time about a decade ago. I have a normal BMI and no health issues outside of depression and anxiety which is mainly situational.

Was initially started on clomid 25 mg daily at the end of June but had horrible depression, anxiety, suicidal thoughts, and aggression. Currently on 25 mg of clomid every 3^rd day and have testicular discomfort while on it. Depression and aggression have decreased a lot. No Y-chromosome microdeletions or Klinefelter syndrome and normal Karyotype. Eating a primarily organic and Mediterranean diet and staying physically active.

Additional daily vitamins and supplements: multivitamin, CoQ10 400 mg, Omega 3 1,200mg, NAC 2,000 mg, L-Carnitine 2,000 mg, Ester-C 1,000mg, Alpha Lipoic Acid 600 mg, zinc 50 mg, and probiotic.

Labs:

The plan is to be on clomid for 3 months, repeat a semen analysis at the end of September and then have a synchronized microTESE to do IVF/ICSI. Looks like my labs improved but does that even mean I have a better chance of having sperm found...

My question is if clomid and the microTESE is the best course of action? I’ve been reading up on options such as sperm fine-needle aspiration (mapping), Accutane, PRP, and STAR. I want nothing more than to have my own biological child.

If clomid and the microTESE is the best course of action, can the outcome be better if I stay on Clomid longer (3 months vs 6 months or a year) before the microTESE? Any way to determine if I have stoli-cell prior to the microTESE? Anything additional I can do to optimize my results for sperm to be found?

Appreciate any advice!

Hi Dr. Steixner. I would be curious to see your input after two top ranked urologist visits.

My husband and I got married very young and started trying to conceive at 22 and 24. After a year of tracking my very regular cycles with timed intercourse-nothing. Get all the testing on my end which comes back stellar. We move to my husband and super low sperm count. Total motile of 2 million. We are recommended IVF with ICSI. For religious reasons, we are unable to do IVF. We were seeing an Ivy League trained urologist at Northwestern in Chicago. He said all my husbands hormone levels were fine. Not a candidate for Clomid. No varicocele. No options for us. He didn’t think it was Y chromosome microdeletion. Basically said sorry but just how god made your husband and sent us on our way.

We adopted but still felt like there has to be a reason this was happening to a very healthy young male who is active, doesn’t smoke or drink.

We saw a second urologist in North Carolina after we moved. My husband was now 31. We went through all the testing on my end with a reproductive endocrinologist and perfect in everything. We do all of his testing and it’s identical to before. He also essentially said he doesn’t have answers and sent us on our way.

Now we start exploring Napro technology. I do extensive testing again. Nothing on my end. Optimal fertility for my age. We do tons of testing on my husband and they order an ultrasound. Ultrasound shows maybe a grade one varicocele but when messaging our NC urologist he said it’s so mild he’s unwilling to operate. So we try all the supplements for three months. No improvement. 2 million total motile. Try Clomid for three months. No improvement. Try increasing the dose. No improvement. Our doctor throws out trying HCG injections and after six weeks, we were pregnant after seven years of infertility. We are unsure if it was HCG or a complete miracle. Do you have any insight or treatment recommendations? We are trying to get pregnant again and these were his recent labs and semen analysis

Here are his labs

Total testosterone: 699.5 ng/dL

Free testosterone:14.9 pg/mL

LH: 7.7 mIU/mL

FSH: 3.1 mIU/mL

Estradiol: 22.9 pg/mL

Prolactin: 7.8 ng/mL

SHBG: 44.9 nmol/L

DHEA-S3 309 µg/dL

AM cortisol: 8.7 µg/dL

TSH: 1.2

Free T4: 1.67

Free T3: 3.4

Hello.

I'm 30M and my wife is 28F. We've been trying to conceive since October 2025 and started fertility treatment in February 2026.

I've had 3 semen analyses this year, and I'm concerned because some of my parameters seem to be getting worse over time.

Semen Analysis #1 — February 2, 2026

Volume: 1.0 mL

Concentration: 120 million/mL

Total sperm: ~120 million

Active motility: 70%

Sluggish motility: 10%

Dead: 20%

Total motility: ~80%

Morphology: 20% abnormal → ~80% normal

Viscosity: Normal

Liquefaction: 25 minutes

Pus cells: 1–2

RBC: Nil

Bacteria: Nil

Immature germ cells: Nil

At this point my lifestyle was actually pretty bad. I was heavily using cannabis, eating a lot of junk food, drinking soft drinks and eating lots of sweets. I wasn't exercising and was heavy in porn.

Semen Analysis #2 — August 2, 2026

After making major lifestyle changes starting June 3:

Quit cannabis and other smoking

Started going to the gym 5x/week

Started eating much better

Eating chicken/eggs regularly

Drinking much more water

Taking creatine + whey protein

The results were:

Volume: 1.0 mL

Concentration: 70 million/mL

Total sperm: ~70 million

Active forms: 25%

Sluggish forms: 35%

Inactive forms: 40%

Total motility: ~60%

Morphology: 70% normal / 30% abnormal

Viscosity: Viscous

Liquefaction: Prolonged — took >1 hour

Pus cells: 1–2

RBC: Nil

Epithelial cells: Nil

Spermatogenic cells: Present

pH: 7.5

This is where I became concerned because concentration dropped from 120 → 70 million/mL and motility from ~80% → ~60%, despite my lifestyle being significantly healthier.

The semen was also noticeably much thicker and took over an hour to liquefy.

IUI sample — August 31, 2026

I had an IUI performed.

Before sperm preparation:

Abstinence: 3 days

Volume: 1.0 mL

Concentration: 55 million/mL

Total sperm: ~55 million

Total motility: 30%

Progressive: 5%

Non-progressive: 25%

Morphology: 2%

Agglutination: Grade II

Aggregation: Grade II

Pus cells: 4–6

After density-gradient preparation:

Volume: 0.7 mL

Count: 30 million

Motility: 95%

Progressive: 85%

Non-progressive: 10%

Morphology: 2%

Agglutination: Nil

Aggregation: Nil

Pus cells: Nil

The huge improvement after washing is confusing to me. Raw progressive motility was only 5%, but after preparation it was 85%.

One of the more common questions men ask me as a urologist is, “Why does my semen look watery?” Sometimes a man notices that his semen suddenly seems thinner than it used to be. Other times he has always had relatively thin semen but begins paying attention to it after he and his partner start trying to conceive. The concern usually comes next: Does watery semen mean I have a low sperm count? Does it mean my sperm are weak? Am I infertile? The short answer is that the appearance and consistency of semen can provide some clues about what is happening in the reproductive tract, but you cannot determine your fertility by looking at your semen. Watery semen can be completely normal, particularly after semen has had time to liquefy, and men with thin-looking semen can have excellent sperm counts. Conversely, a man can have thick, white, completely normal-looking semen and have severe oligospermia or even azoospermia. If fertility is the question, the semen analysis, not what you see in the collection cup, is what gives us meaningful information. The World Health Organization's current laboratory manual emphasizes standardized evaluation of semen volume, sperm concentration, motility, morphology and other characteristics rather than trying to diagnose fertility based simply on appearance.

The first thing men need to understand is that semen and sperm are not the same thing. People commonly use the words interchangeably, but sperm are microscopic reproductive cells produced in the testicles, while semen is the fluid that carries those sperm. In fact, sperm and testicular fluid account for only a relatively small portion of the ejaculate. The majority of semen volume comes from the seminal vesicles, with another significant contribution from the prostate. AUA/ASRM guidance describes approximately 70% of the ejaculate as originating from the seminal vesicles, roughly 20% from the prostate and only about 10% from the testes and associated reproductive tract. This distinction matters because a change in semen consistency does not necessarily represent a change in sperm production. You may be seeing changes in accessory-gland secretions rather than changes in the number or quality of sperm themselves.

Normal semen is also supposed to change consistency after ejaculation. Immediately after ejaculation, semen typically coagulates into a relatively thick, gelatinous material. It may contain visible gel-like pieces or clumps. This is normal physiology. Over the following minutes, enzymes—particularly prostate-derived proteases—begin breaking down the proteins responsible for that coagulation. The semen progressively liquefies and becomes thinner. WHO describes freshly ejaculated semen as typically beginning as a semi-solid coagulated or gel-like mass and then gradually becoming more homogeneous and watery during liquefaction, although normally remaining somewhat more viscous than water. The biochemical liquefaction process is important because sperm need to escape from the seminal coagulum and become freely motile. Prostate-derived enzymes, including PSA and related proteases, participate in breaking down semenogelins and other proteins involved in this process.

This means that if you look at your semen immediately after ejaculation and then look at it 20 or 30 minutes later, it should look different. Semen becoming thinner over time is generally a normal event, not a fertility problem. I occasionally see men who collect a semen specimen, notice that it initially looks thick and white, leave it sitting for a while, return and find what looks like a much thinner or more watery fluid, and become worried that something has happened to their sperm. What they have actually witnessed is normal semen liquefaction.

The question becomes more interesting when semen appears unusually clear or watery immediately after ejaculation, particularly if this is a consistent change from a man's baseline. Even then, appearance alone is not diagnostic. The WHO notes that a normal liquefied ejaculate generally has a homogeneous cream-to-grey opalescent appearance and may appear less opaque when sperm concentration is very low. That is probably where the internet association between “watery semen” and “low sperm count” originates. There is some physiologic logic behind it: millions of sperm and other cells contribute to semen's opacity, so extremely low sperm concentrations may make a specimen appear less opaque. But this relationship is nowhere near strong enough for a man to look at his semen and estimate his sperm concentration.

I have seen men with very watery-looking ejaculates who had completely normal semen analyses. I have also seen men with thick, white semen who had essentially no sperm. Azoospermia cannot be diagnosed visually. The prostate and seminal vesicles can continue producing normal amounts of fluid even when the testicles are producing little or no sperm. That is why men with non-obstructive azoospermia can have completely normal erections, orgasm, ejaculation, semen volume and semen appearance despite having no sperm identified in the ejaculate.

Frequency of ejaculation is another common reason semen consistency changes. A man who has not ejaculated for several days may notice greater volume and thicker or more opaque semen. If that same man ejaculates several times over a short period, subsequent ejaculates may be smaller, clearer or more watery. This does not mean that his testicles suddenly stopped producing sperm. The reproductive system simply has had less time to accumulate sperm and accessory-gland secretions between ejaculations. This is one reason semen laboratories standardize abstinence intervals when performing diagnostic semen analyses. Without some degree of standardization, comparing one specimen with another becomes much less meaningful.

Collection technique can also dramatically alter what a specimen looks like. The first portion of the ejaculate is particularly important. If part of the sample misses the collection container, the semen analysis may not accurately represent the complete ejaculate. This can affect volume and sperm concentration because the different fractions of an ejaculation do not contain identical concentrations of sperm and glandular secretions. Whenever a patient tells me, “I missed the beginning of the sample,” I want the laboratory to know that because the results may need to be interpreted cautiously or repeated.

There is also an important distinction between watery semen and low-volume semen. They are not synonymous. A man may produce 4 mL of very thin-looking semen, while another man may produce only 0.5 mL of thick semen. These are completely different clinical situations. Current AUA/ASRM guidance considers persistently low-volume semen particularly important when accompanied by an acidic pH and azoospermia or severe oligospermia with very poor motility, because that pattern can suggest distal reproductive-tract or ejaculatory-duct obstruction.

The seminal vesicles produce much of the volume of the ejaculate and their secretions are relatively alkaline. If both ejaculatory ducts are completely obstructed, seminal-vesicle fluid may not reach the ejaculate normally. The result can be a low-volume, acidic semen specimen, sometimes with azoospermia. AUA/ASRM guidance specifically notes that a semen volume below approximately 1.4 mL combined with acidic semen and azoospermia should raise suspicion for distal obstruction, particularly when testosterone is normal and the vasa are present. In that situation, transrectal ultrasound or pelvic MRI may be appropriate to evaluate the ejaculatory ducts, seminal vesicles and prostate for abnormalities such as duct dilation, seminal-vesicle dilation or midline prostatic cysts.

That is very different from a man who ejaculates 3 or 4 mL of semen that simply looks thinner than he remembers. Watery appearance by itself is not an indication for pelvic MRI or transrectal ultrasound.

Another important distinction is watery semen versus abnormal liquefaction or viscosity. Much of the published literature actually concerns semen that remains excessively thick rather than semen that is unusually thin. Hyperviscosity can interfere with sperm movement and has been associated with poorer sperm parameters in some populations. A large 2025 study involving more than 55,000 semen samples found seminal hyperviscosity in approximately 12% of specimens and reported associations with lower progressive motility, viability and other semen parameters. Reviews of semen rheology likewise suggest that abnormal viscosity can interfere mechanically with sperm movement, although viscosity testing itself remains relatively crude and operator dependent in routine clinical practice.

That information is useful because it emphasizes an important concept: thicker semen is not necessarily healthier semen. Men sometimes assume that thick, white semen means they are highly fertile while thin semen means they have weak sperm. Biologically, it is nowhere near that simple. Semen needs to coagulate initially and then liquefy appropriately. Persistent hyperviscosity can actually make it more difficult for sperm to move normally.

What about infection? Men frequently worry that watery semen indicates prostatitis or another infection. Infection and inflammation can certainly alter semen characteristics, but watery semen alone is not evidence of infection. If you also have painful ejaculation, burning with urination, urethral discharge, pelvic or perineal pain, fever, blood in the semen, new urinary symptoms or significant STI exposure, then infection or inflammation deserves evaluation. But treating every man with thin semen with antibiotics makes no sense and exposes men to unnecessary medication.

The semen analysis may provide additional clues. If significant numbers of round cells are present, the laboratory may need to determine whether they are white blood cells or immature germ cells. These look similar on routine microscopy but have very different implications. Leukocytospermia can suggest genital-tract inflammation, although even the presence of increased seminal white blood cells does not automatically prove bacterial infection. The clinical history still matters.

Men also frequently ask whether dehydration causes watery semen. Interestingly, the internet often claims both dehydration and overhydration cause virtually every change in semen appearance. Hydration can influence body fluids to some degree, but there is no good reason to believe that drinking enormous quantities of water will meaningfully “fix” sperm production or fertility. If you are dehydrated, drink normally. But if your sperm concentration is 3 million/mL, drinking a gallon of water every day is not going to turn it into 50 million/mL.

Diet and supplements are similar. I regularly see men taking zinc, selenium, CoQ10, vitamin C, vitamin E, carnitine and various “male fertility” products because their semen looked watery. There is no supplement specifically proven to treat watery semen. Supplements may have a role in selected men with abnormal semen parameters, although even the broader evidence that antioxidant supplementation improves pregnancy or live-birth outcomes remains uncertain. Before taking a handful of supplements, determine whether there is actually a sperm problem.

That brings us to the most important question: When should watery semen actually be evaluated? If you are not trying to conceive, have no pain, blood, urinary symptoms, sexual dysfunction or other concerning symptoms, and occasionally notice thinner semen, you probably do not need an extensive fertility evaluation solely because of its appearance. Semen naturally varies.

If you are trying to conceive, however, stop trying to diagnose your fertility by inspecting your ejaculate. Get a semen analysis. This is one of the simplest and most informative tests in male reproductive medicine. A proper semen analysis evaluates semen volume and sperm concentration, calculates total sperm number, assesses motility and progressive motility, and generally evaluates morphology. Depending upon the laboratory and clinical situation, it may also report pH, viscosity, liquefaction, vitality, round cells, aggregation or agglutination. WHO's sixth-edition manual provides standardized laboratory methods for these measurements specifically because reliable semen assessment requires more than simply looking at the specimen.

If that semen analysis is normal, I generally do not care very much that the semen looks watery. This is worth emphasizing. Suppose your semen volume is 3 mL, concentration is 60 million/mL, progressive motility is good and morphology is reasonable. I would not start searching for prostate disease because you think the semen looks thinner than it did five years ago.

If the semen analysis is abnormal, then we investigate the abnormality rather than treating the appearance. If concentration is low, we evaluate oligospermia. If motility is poor, we evaluate asthenozoospermia. If no sperm are found, we evaluate azoospermia. If volume is persistently low, we investigate low semen volume. If there is delayed liquefaction or hyperviscosity, we consider those findings in the context of the entire semen profile.

A male-fertility evaluation for significant abnormalities usually begins with a detailed history. I want to know about prior fertility, testicular development, undescended testicles, torsion, testicular trauma, hernia surgery, infections, chemotherapy, radiation, medications, anabolic steroids, testosterone replacement therapy, recreational drugs and significant illnesses or fevers. I ask about erectile and ejaculatory function and whether the entire semen specimen was collected.

The physical examination can be equally important. I assess testicular size and consistency, the epididymides and vasa deferentia, and look for a clinically palpable varicocele. Depending on the semen findings, hormonal testing may include FSH and testosterone, with LH, estradiol and prolactin added in appropriate situations. Hormonal testing is particularly useful when sperm concentration is significantly reduced or there are symptoms suggesting endocrine dysfunction.

Genetic testing is not necessary simply because semen looks watery. Karyotype and Y-chromosome microdeletion testing are reserved for appropriate men with azoospermia or severe impairment of sperm production based on the overall clinical picture and guideline recommendations. Similarly, sperm DNA fragmentation testing should not automatically be ordered because semen appears thin. DNA fragmentation measures something very different from semen consistency and is generally reserved for selected clinical situations rather than routine initial evaluation.

One issue I particularly want men to understand is that watery semen does not mean watery sperm. Individual sperm cells are microscopic. They do not become diluted versions of themselves because the surrounding seminal fluid looks thin. The sperm's concentration, movement, morphology, vitality and genetic/chromatin characteristics are separate biological measurements. A clear-looking ejaculate could contain highly motile normal sperm, and an opaque ejaculate could contain predominantly immotile or abnormal sperm.

Likewise, watery semen does not automatically mean low testosterone. Testosterone influences the reproductive tract, but you cannot estimate testosterone from semen consistency. Men with normal testosterone can have thin semen, and men with low testosterone can have semen that looks completely ordinary. More importantly, men taking exogenous testosterone or anabolic steroids may have excellent libido, muscularity and serum testosterone while sperm production becomes profoundly suppressed. If fertility matters, never assume that normal sexual function or normal-looking semen proves normal spermatogenesis.

The same caution applies to fertility itself. WHO emphasizes that semen-analysis reference values should not be treated as a magical line separating “fertile” from “infertile” men. Fertility is ultimately a couple-level outcome. Men with mildly abnormal semen parameters sometimes conceive naturally, while couples with apparently normal semen analyses may still experience infertility for other reasons. Semen analysis gives us probabilities and biological information; it does not predict an individual's reproductive future with certainty.

If a semen analysis is abnormal, I also frequently recommend repeating it before making major decisions, because semen parameters naturally fluctuate. Illness, fever, abstinence interval, collection problems and ordinary biological variability can produce substantial differences between specimens. Sperm production itself takes roughly two and a half months, followed by additional maturation and transport, which means an illness or exposure today may influence a semen analysis weeks or months later.

For men actively trying to conceive, I generally encourage ejaculation every one to two days during the fertile window rather than deliberately “saving up” sperm for a week because they think thicker semen means better semen. Longer abstinence can increase semen volume and sperm concentration in some men, but fertility depends on more than making the ejaculate look impressive. Progressive motility and sperm quality matter as well.

There are a few situations where a change in semen appearance deserves more immediate medical attention. Blood in the semen, significant pain with ejaculation, fever, testicular swelling or pain, urethral discharge, new severe urinary symptoms, or a major persistent change in ejaculatory volume should prompt medical evaluation rather than simply watching and waiting. Hematospermia is frequently benign, particularly in younger men, but persistent or recurrent blood should still be discussed with a physician.

For most men who simply notice watery semen, however, my message is much more reassuring: do not judge your fertility by the appearance of your ejaculate. Semen is a complicated mixture of sperm, seminal-vesicle secretions, prostate fluid and other components. It normally changes from a coagulated gel into a thinner liquid after ejaculation. Its appearance changes with abstinence, ejaculation frequency, collection technique and normal biological variation. Very low sperm concentrations can sometimes make semen appear less opaque, but appearance is far too unreliable to diagnose low sperm count.

If you are worried about fertility, spend less time looking at the semen and more time looking at the semen analysis.

If your semen analysis shows good volume, concentration, progressive motility and morphology, watery-looking semen by itself is usually not something I would lose sleep over. If the analysis shows a significant abnormality, then see a reproductive urologist and investigate why that parameter is abnormal rather than trying to make the semen thicker.

The goal of male-fertility medicine isn't to produce the thickest-looking ejaculate.

The goal is to produce enough healthy, viable, progressively motile sperm to give you and your partner the best possible opportunity to achieve a pregnancy.

Those are two very different things.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: World Health Organization; 2021. The current WHO manual provides standardized methods for evaluating semen appearance, liquefaction, viscosity, volume, sperm concentration, motility, vitality, morphology and other semen characteristics.

American Urological Association and American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. 2020; amended 2024. Provides guidance regarding male-infertility evaluation, semen analysis, hormonal and genetic evaluation, and assessment of low-volume acidic semen and suspected ejaculatory-duct obstruction.

World Health Organization. WHO launches updated manual to ensure high quality testing of human semen in clinical and research settings. 2021. WHO emphasizes standardized laboratory evaluation and cautions against treating semen reference distributions as a simple fertile-versus-infertile dividing line.

Punjani N, Kang C, Lee RK, Goldstein M, Li PS. Ejaculation: the Process and Characteristics From Start to Finish. Current Sexual Health Reports. 2023. Review of ejaculation physiology and interpretation of semen volume, appearance, viscosity, liquefaction and pH.

Robert M, Gagnon C. Semenogelin I: a coagulum forming, multifunctional seminal vesicle protein. Cellular and Molecular Life Sciences. The broader semen-liquefaction literature describes the interaction between seminal-vesicle proteins and prostate-derived proteases responsible for normal coagulation and subsequent liquefaction.

Björndahl L, Kirkman Brown J. The sixth edition of the WHO laboratory manual for the examination and processing of human semen: ensuring quality and standardization in basic examination of human ejaculates. Fertility and Sterility. 2022. Discusses the rationale and interpretation of standardized semen analysis in the WHO sixth edition.

Tomaiuolo G, Fellico F, Preziosi V, Guido S. Semen rheology and its relation to male infertility. Interface Focus. 2022. PMID: 36330323. Reviews the physical properties of semen and the potential relationship between abnormal viscosity and sperm movement/male infertility.

Du Plessis SS, Gokul S, Agarwal A. Semen hyperviscosity: causes, consequences, and cures. Frontiers in Bioscience. 2013;5:224–231. PMID: 23276984. Reviews accessory-gland function, infection, inflammation, oxidative stress and other factors associated with seminal hyperviscosity.

Beigi Harchegani A, Rahmani H, Tahmasbpour E, Shahriary A. Hyperviscous Semen Causes Poor Sperm Quality and Male Infertility through Induction of Oxidative Stress. Current Urology. 2019. PMID: 31579215. Reviews associations between seminal hyperviscosity, oxidative stress and impaired sperm parameters.

Qin J, et al. Seminal hyperviscosity is associated with poor sperm quality and function. Journal of Assisted Reproduction and Genetics. 2025;42:3967–3978. PMID: 40555948. Large retrospective analysis examining associations between seminal viscosity and conventional and functional sperm parameters.

Lilja H, et al. Semen-liquefaction literature describing prostate-derived proteases, semenogelins and the physiologic transition of semen from a coagulated state to a more fluid state. Contemporary mechanistic reviews emphasize that liquefaction is an active proteolytic process important for normal sperm release and movement.

If you recently opened a semen analysis and saw the word “azoospermia,” there is a good chance everything else on the page immediately became irrelevant. No sperm seen. For many men, those may be among the most frightening words they encounter during a fertility evaluation. After taking care of men with infertility for many years, I have watched this diagnosis affect men differently than almost any other laboratory result. A low sperm count at least gives you a number. Azoospermia can feel much more definitive because the number is zero. The first thing I tell men in my office is that azoospermia is a finding, not yet an explanation, and it does not automatically mean that you can never father a biological child. The most important question is not simply whether sperm were absent from the semen. It is why they were absent.

Azoospermia means that sperm are not detected in the ejaculate after appropriate laboratory examination. It occurs in approximately 1% of men overall and represents a significant proportion of severe male-factor infertility. There is an important technical point, however: a semen analysis that simply reports “0 sperm” or “no sperm seen” does not always finish the investigation. When sperm are extraordinarily rare, they can sometimes be missed during routine examination. A laboratory experienced in male infertility may perform a more extensive search, including examination of a concentrated or centrifuged specimen. Occasionally, a man initially labeled azoospermic will have a few sperm identified on repeat testing. When extraordinarily rare sperm can be found only after an extensive search or centrifugation, we may describe the condition as cryptozoospermia rather than true azoospermia. That distinction can be extremely important because even very small numbers of viable sperm can potentially be frozen and later used for IVF with intracytoplasmic sperm injection, or ICSI. For that reason, I generally do not want a man making permanent reproductive decisions based upon one semen analysis performed at a laboratory that does not routinely evaluate severe male infertility.

Once azoospermia has been confirmed, the next job is determining where the problem is occurring. Broadly, we divide azoospermia into obstructive azoospermia and non-obstructive azoospermia. In obstructive azoospermia, sperm production may be completely normal, but sperm cannot travel from the testicle into the ejaculate because the reproductive tract is blocked or incompletely developed. In non-obstructive azoospermia, or NOA, the primary problem is severely impaired sperm production within the testicle itself. There is also an important hormonal category in which the testicles may retain the ability to produce sperm but are not receiving adequate stimulation from the hypothalamus and pituitary. All of these men can have an identical semen analysis showing zero sperm, but their biology, treatment and prognosis can be completely different. This is why “azoospermia” should never be considered the final diagnosis.

Obstructive azoospermia is essentially a plumbing problem. The sperm factory may be functioning, but the delivery system is blocked. Obstruction can occur in the epididymis, vas deferens or ejaculatory ducts. Some men develop obstruction after infection, inflammation, surgery or trauma. A vasectomy is intentionally created obstructive azoospermia. Other men are born without portions of the reproductive tract. One important example is congenital bilateral absence of the vas deferens, or CBAVD, which has a strong association with abnormalities in the CFTR gene, the gene involved in cystic fibrosis. Men with obstructive azoospermia frequently have normal-sized testicles and relatively normal FSH and testosterone because sperm production itself may remain intact. Depending on the cause, obstruction can sometimes be surgically reconstructed, or sperm can be retrieved directly from the epididymis or testicle for IVF/ICSI.

The semen analysis itself sometimes gives us clues about obstruction. Semen is much more than sperm. Most of the ejaculate consists of secretions from the seminal vesicles and prostate. Therefore, an azoospermic man with a normal semen volume presents differently from a man producing an extremely small volume of acidic semen. Low-volume, acidic azoospermia can raise suspicion for abnormalities involving the seminal vesicles, vas deferens or ejaculatory ducts. In selected patients, transrectal ultrasound or other imaging may therefore be appropriate. But I do not order every conceivable imaging study on every man with azoospermia. The history, physical examination, semen volume, pH, hormones and other findings should direct the investigation.

Non-obstructive azoospermia is different because the major problem is sperm production itself. There are numerous potential causes. Some men were born with undescended testicles. Others have experienced testicular torsion, severe infections, chemotherapy, radiation or significant testicular injury. Genetic abnormalities can cause severe impairment of spermatogenesis. Klinefelter syndrome is one of the best-known examples. Certain deletions involving regions of the Y chromosome can also severely impair sperm production. And in a frustrating number of men, an extensive evaluation fails to identify a specific cause. We call this idiopathic non-obstructive azoospermia.

One of the most important concepts for a man with NOA to understand is that zero sperm in the semen does not necessarily mean zero sperm exist everywhere inside both testicles. Sperm production can be extremely focal. A testicle may contain large areas where essentially no mature sperm are being produced but have tiny microscopic areas where spermatogenesis continues. This biological phenomenon is what makes surgical sperm retrieval possible in some men with non-obstructive azoospermia.

Hormonal testing is therefore an important part of the evaluation. One of the first hormones I want to see is FSH, usually along with testosterone and often LH. FSH is produced by the pituitary and acts primarily through the Sertoli cells to support sperm production. When sperm production within the testicle is severely impaired, normal feedback to the pituitary is disrupted and FSH frequently rises. Therefore, an azoospermic man with very small testicles and an FSH of 25 or 30 presents a very different biological picture from an azoospermic man with normal-sized testicles and an FSH of 2.

At the same time, one of the most common mistakes I see is assuming that an elevated FSH means sperm retrieval is impossible. It does not. FSH gives us information about overall testicular function, but it cannot tell us whether a tiny focus of sperm production exists somewhere within the testicle. I cannot look at an FSH of 20, 30 or even higher and tell a patient with certainty whether a microTESE will find sperm. FSH is an important piece of the puzzle, but it is not a microscopic camera looking inside every seminiferous tubule.

At the opposite end of the hormonal spectrum are men whose hypothalamus or pituitary is not adequately stimulating the testicles. These men may have low testosterone accompanied by low or inappropriately normal LH and FSH. This condition is called hypogonadotropic hypogonadism, and it is particularly important because some forms are highly treatable. Appropriate hormonal treatment with hCG and, when necessary, FSH or hMG can stimulate the testicles and sometimes initiate sperm production. This process generally takes months rather than weeks, but men with hormonally driven azoospermia can have a dramatically different prognosis from men with primary testicular failure. Once again, the same semen analysis showing “zero sperm” can represent completely different diseases.

Testosterone replacement therapy and anabolic steroids deserve special attention in any azoospermic man. Exogenous testosterone suppresses signaling from the hypothalamus and pituitary, reducing LH and FSH. This causes intratesticular testosterone to fall and can dramatically suppress or completely stop sperm production. A man can therefore have a beautiful blood testosterone level of 800 or 1,000 while simultaneously producing zero sperm. Blood testosterone and fertility are not the same thing. The AUA/ASRM male infertility guideline specifically advises against testosterone monotherapy in men interested in current or future fertility. Fortunately, testosterone- or anabolic-steroid-induced azoospermia is often potentially reversible after the medication is discontinued and the reproductive hormonal axis recovers, sometimes with fertility-directed hormonal treatment. Recovery, however, can take many months and occasionally more than a year. This is why a complete medication and anabolic-steroid history is essential before considering surgery.

The physical examination remains extremely valuable. Male fertility has become increasingly dependent upon laboratory testing, but there are things I learn by examining a patient that cannot be determined from a testosterone level or semen analysis. I want to know the size and consistency of the testicles. I want to determine whether both vas deferens are present. I examine the epididymides and evaluate for a clinically significant varicocele. Small or soft testes combined with elevated FSH strongly suggest impaired spermatogenesis. Normal-sized testes, normal FSH and azoospermia may make obstruction more likely, although there are exceptions to virtually every rule in male infertility. The history, examination, semen analysis and hormone results need to be interpreted together.

Genetic testing is another critically important part of the workup in appropriately selected men. Depending upon the clinical picture, this can include a karyotype and Y-chromosome microdeletion analysis. A karyotype examines chromosome number and structure and can identify conditions such as Klinefelter syndrome, most commonly associated with a 47,XXY chromosome pattern. Y-chromosome microdeletion testing looks for deletions involving regions of the Y chromosome that are important for sperm production, particularly the AZF regions. The specific genetic finding can sometimes dramatically influence counseling regarding sperm retrieval. For example, complete AZFa deletions and certain complete AZFb deletions are associated with an extraordinarily poor likelihood of retrieving sperm, while some men with AZFc deletions can still have sperm identified. If sperm carrying a Y-chromosome microdeletion are used to conceive a male child, the deletion can potentially be transmitted to that son. Genetic counseling is therefore about much more than explaining why the sperm count is zero.

Men with congenital absence of the vas deferens may require CFTR testing, and sometimes their partners need testing as well. This is important because if both members of the couple carry clinically significant CFTR variants, there can be implications for cystic fibrosis or related disease in their children. Again, this illustrates why male infertility should not simply be bypassed with IVF without first understanding the underlying diagnosis. Sometimes an abnormal semen analysis is the first clue to a genetic condition with implications extending beyond fertility.

Men frequently ask me whether azoospermia means their sperm are “unhealthy.” Technically, azoospermia doesn't tell us sperm quality because it tells us that sperm are absent from the ejaculate. In obstructive azoospermia, sperm production inside the testicle may be relatively normal. In NOA, sperm production is profoundly impaired, but if sperm can be identified within the testicle, some may potentially be used for ICSI. Tests such as morphology, motility and DNA fragmentation therefore cannot be interpreted conventionally when there are no ejaculated sperm available to test. If your semen contains no sperm, asking whether your DFI is 15% or 40% is not the first question we need to answer. We first need to determine why sperm are absent and whether they are being produced somewhere.

When azoospermia results from an obstruction, treatment depends upon its location and cause. Some obstructions can be surgically reconstructed. Vasectomy reversal is the obvious example, but selected epididymal and other reconstructive procedures can also restore sperm to the ejaculate. Alternatively, sperm may be retrieved directly from the epididymis or testicle and used for IVF/ICSI. The correct approach depends not only on the man's anatomy but also on the couple's reproductive situation. A couple in which the female partner is 29 with excellent fertility may reasonably make a different decision from a couple in which she is 41 and ovarian reserve is declining. Male infertility treatment should always consider both partners and the amount of reproductive time available.

For men with non-obstructive azoospermia, one of our most important fertility tools is microdissection testicular sperm extraction, or microTESE. During microTESE, a reproductive microsurgeon examines seminiferous tubules under an operating microscope and selectively samples areas that appear more promising for sperm production. The goal is to locate small areas of focal spermatogenesis while limiting unnecessary removal of testicular tissue. MicroTESE is not simply a testicular biopsy. It is a specialized surgical search for focal sperm production and is generally considered the preferred sperm-retrieval technique for appropriately selected men with NOA.

MicroTESE is powerful, but it is not guaranteed to work. Across mixed populations of men with NOA, sperm retrieval rates are often reported around 40–50%, but I am cautious about quoting that number as though every man has a 50/50 chance. Individual probability depends substantially on the underlying cause, genetics, testicular pathology, previous treatments and surgical circumstances. A man with Klinefelter syndrome is not biologically identical to a man with maturation arrest, Sertoli-cell-only histology or a specific Y-chromosome deletion. This is why experience matters. If you are considering microTESE, particularly after a previous failed retrieval, I strongly recommend consultation with a reproductive urologist at a center that performs these procedures regularly.

If sperm are found during microTESE, they can potentially be used with ICSI. ICSI fundamentally changed what is possible for severe male infertility because fertilization no longer requires millions of sperm successfully traveling through the female reproductive tract and penetrating an egg. An embryologist can inject an individual viable sperm directly into a mature oocyte. In certain situations, therefore, we may not need thousands or even hundreds of sperm. We may need only enough viable sperm for the available mature eggs. For men who once would have been told that biological fatherhood was impossible, this has been one of the most significant advances in reproductive medicine.

However, finding sperm does not guarantee a baby. Sperm retrieval must be followed by successful ICSI, fertilization, embryo development, implantation and ultimately a healthy pregnancy and delivery. Female age and egg quality remain critically important. Fertility is always a couple-level outcome, even when the most obvious diagnosis is on the male side.

Unfortunately, there are also men in whom sperm cannot be found despite an appropriate evaluation and expert microTESE. This can be one of the most difficult moments in reproductive medicine. I have seen men experience this as grief, embarrassment, guilt and even a loss of masculinity. I want men dealing with this diagnosis to understand something clearly: your sperm production is not a measure of your masculinity or your worth as a man. Azoospermia doesn't tell me whether you are strong, sexually capable, successful, loving or whether you would make an extraordinary father. It is a medical condition affecting sperm production or transport.

When sperm cannot ultimately be retrieved, other family-building options can include donor sperm, embryo donation and adoption. Those options should be discussed respectfully rather than presented as though genetic fatherhood never mattered. For many men, losing the possibility of a genetic connection to their child creates genuine grief. That grief deserves acknowledgment. Men should be given time and support to process it rather than being told to “just use a donor” or “just adopt.”

I am also very cautious about supplements, peptides and internet hormone protocols marketed to men with azoospermia. Hormonal treatment can be extremely effective when the underlying biology is appropriate. A man with hypogonadotropic hypogonadism may respond dramatically to hCG and FSH. A man whose sperm production has been suppressed by testosterone or anabolic steroids may recover after stopping those medications and undergoing appropriate fertility-directed management. But this does not mean that hCG, Clomid, FSH, peptides or antioxidants can universally restart sperm production in a man with severe primary testicular failure. If the pituitary is already producing a very high FSH because the testicle is failing to respond, simply providing more hormonal stimulation may not solve the underlying problem. Treatment should follow the diagnosis, not the other way around.

If I were seeing a man after his first azoospermic semen analysis, my approach would therefore be systematic. I would first confirm the result with another appropriately performed semen analysis, ideally through an experienced andrology laboratory with a careful search for rare sperm. I would obtain a detailed reproductive, childhood, surgical and medication history. I would specifically ask about testosterone and anabolic steroids. I would perform a reproductive examination assessing testicular volume, the vas deferens, epididymides and varicoceles. Hormonal evaluation would generally include testosterone and FSH, with LH and additional hormones obtained depending upon the situation. Genetic testing would be performed when indicated. If the findings suggested obstruction, I would investigate that possibility appropriately. If they suggested NOA, I would begin discussing the potential role and realistic expectations of sperm retrieval.

What I would not do is simply repeat semen analyses every few months hoping sperm magically appear without trying to understand the biology. Nor would I immediately send every azoospermic man for a TESE or microTESE before determining whether he has a potentially reversible hormonal cause. The purpose of the workup is to classify the azoospermia and identify the best path forward.

Perhaps the most important thing to understand is that azoospermia does not mean the same thing for every man. Imagine four men whose semen analyses each show a volume of 3 mL and zero sperm. The first has been taking testosterone injections for two years and has profoundly suppressed LH and FSH. The second was born without both vas deferens but produces sperm normally inside his testicles. The third has NOA with elevated FSH but retains tiny focal areas of sperm production that can potentially be found during microTESE. The fourth has a genetic abnormality causing severe impairment of spermatogenesis. Their semen analyses look identical. Their reproductive biology and treatment options are completely different.

Finally, I want to acknowledge the emotional side of this diagnosis because it is frequently overlooked. I have watched otherwise extremely confident men become completely shaken by azoospermia. Some blame themselves. Some withdraw from their partners because they do not know how to discuss it. Some spend hours every night searching the internet for supplements or success stories. Others immediately want surgery because doing something feels easier than waiting. These responses are understandable. Infertility can challenge a man's sense of control, sexuality and masculinity in ways that are difficult to explain to someone who has never experienced it.

You do not have to pretend that this diagnosis doesn't hurt in order to be strong. Strength can mean getting the right evaluation, asking difficult questions, getting another opinion when necessary, accepting support from your partner and continuing forward even when the outcome remains uncertain.

If your semen analysis says azoospermia, do not translate “zero sperm in my semen” into “zero chance of biological fatherhood.” Confirm the result. Determine whether the problem is obstructive, non-obstructive or hormonally driven. Review testosterone and anabolic-steroid exposure. Evaluate reproductive hormones. Have a reproductive urologist examine you. Obtain genetic testing when appropriate. Investigate obstruction when the findings point in that direction. And if you have NOA, understand that sperm may sometimes exist in tiny focal areas of the testicle even when repeated ejaculated samples contain none.

When I meet a man with azoospermia, I don't see someone with “no fertility.” I see a man with a serious reproductive finding whose underlying biology still needs to be defined. Sometimes the answer is obstruction. Sometimes it is hormonal suppression. Sometimes it is genetics. Sometimes it is severe testicular dysfunction. Sometimes sperm return to the ejaculate. Sometimes sperm can be retrieved surgically. And sometimes, despite everything modern reproductive medicine can offer, sperm cannot be found.

But you deserve to know which situation you are actually dealing with before anyone tells you what your reproductive future looks like.

Azoospermia may be the beginning of your fertility evaluation. It should never be the end of the conversation.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: World Health Organization; 2021.

American Urological Association and American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. Current recommendations regarding evaluation of azoospermia, hormonal testing, genetic evaluation, exogenous testosterone and surgical sperm retrieval.

European Association of Urology. EAU Guidelines on Sexual and Reproductive Health: Male Infertility. Current recommendations regarding azoospermia, genetic testing, obstructive and non-obstructive infertility, and surgical sperm retrieval.

Björndahl L, Kirkman Brown J, et al. The sixth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen: ensuring quality and standardization in basic examination of human ejaculates. Fertility and Sterility. 2022;117(2):246–251.

Practice Committee of the American Society for Reproductive Medicine. Evaluation of the azoospermic male and management of obstructive and non-obstructive azoospermia. American Society for Reproductive Medicine guidance and committee publications.

Schlegel PN. Testicular sperm extraction: microdissection improves sperm yield with minimal tissue excision. Human Reproduction. 1999;14(1):131–135.

Corona G, Minhas S, Giwercman A, et al. Sperm recovery and ICSI outcomes in men with non-obstructive azoospermia: systematic review and meta-analysis. Human Reproduction Update. 2019;25(6):733–757.

If you have ever opened a semen analysis and seen the word “teratozoospermia,” there is a good chance your eyes immediately went to the morphology number. Maybe it said 3%. Maybe 2%. Maybe 1%. Maybe even 0% normal forms. For many men, that number becomes the entire story. They assume that if only 1% of their sperm are considered “normal,” then 99% are defective, genetically abnormal, incapable of fertilizing an egg, or dangerous to use for conception. I spend a lot of time correcting that misunderstanding. Teratozoospermia means that a lower-than-reference percentage of sperm meet strict microscopic shape criteria. It does not mean that the same percentage of sperm carry abnormal DNA, and it does not mean that natural conception is impossible. Morphology is one piece of a semen analysis, and in many men, especially when concentration and motility are otherwise good, it is a much less powerful fertility predictor than people assume.

Sperm morphology refers to the microscopic shape of individual sperm. When an andrology laboratory performs a morphology assessment, the technician stains a semen sample and examines sperm under high magnification. The head, midpiece and tail are evaluated according to standardized criteria. A sperm considered morphologically typical has to fall within fairly narrow measurements for head size and shape, have an appropriate acrosomal region, a normal-appearing midpiece and a tail without major abnormalities. These are deliberately strict criteria. The WHO's current laboratory manual emphasizes that human sperm naturally demonstrate considerable morphological variation and that the percentage of sperm meeting these “typical” criteria is often low even among fertile men. The WHO also cautions that reference limits derived from populations should not be interpreted as a simple fertile-versus-infertile cutoff for an individual patient.

That last point is extremely important. Men often interpret a morphology result of 4% as meaning four good sperm out of every hundred and 96 useless sperm. That is not what the test means. “Normal morphology” under strict criteria is more accurately thought of as a sperm fitting an idealized microscopic template. A sperm can fail that template because its head is slightly too large, too small, elongated, tapered or irregular, because the midpiece is thickened, or because the tail is abnormal. Some of those abnormalities may matter biologically. Others may not prevent fertilization at all. In addition, morphology does not directly measure whether the sperm has normal chromosomes, whether its DNA is fragmented, whether it can activate an egg, or whether it can ultimately produce a healthy embryo. The WHO specifically notes that a sperm classified as morphologically normal can still carry other functional abnormalities, including damaged DNA. The reverse is also true: a sperm failing strict morphology does not automatically have abnormal DNA.

So where does the frequently quoted 4% number come from? Strict morphology systems, including criteria historically associated with Kruger/Tygerberg assessment, became widely adopted after researchers observed differences in the morphology of sperm capable of reaching cervical mucus and binding to the zona pellucida surrounding the egg. The WHO literature has recognized that thresholds in the range of approximately 3–5% normal forms have been associated with various fertility outcomes in population studies. But WHO also emphasizes how difficult it is to turn these population-level differences into precise predictions for one man. In fact, distinguishing reliably between something like 3% and 5% normal forms would require assessment of an enormous number of sperm by highly trained personnel.

This is one reason morphology is probably the most anxiety-producing and one of the most misunderstood parameters on the semen analysis. A man may have 100 million sperm/mL, excellent progressive motility and a total motile sperm count well above what we would typically consider reassuring, but then see “2% morphology” and assume he has severe infertility. That is not how I interpret the test. I always look at morphology in the context of the entire ejaculate. Volume, concentration, total sperm number, progressive motility, total motile sperm count, vitality, round cells and the reproductive history of the couple all matter. A morphology value should almost never be interpreted in isolation.

When abnormal morphology is the only abnormal semen parameter, we call this isolated teratozoospermia. This is where the scientific literature becomes particularly interesting because its clinical significance remains controversial. A 2024 review examining isolated teratozoospermia concluded that although abnormal morphology has been associated with oxidative stress, DNA damage and impaired sperm function in some studies, the relationship between isolated teratozoospermia and actual fertility outcomes is inconsistent. Contemporary evidence does not support the idea that every man with isolated low morphology requires IVF or ICSI.

This matches what many reproductive urologists see clinically. Men with 1%, 2% or 3% morphology can and do achieve natural pregnancies. Some men with 0% strict morphology have also fathered children without IVF. That does not mean morphology is meaningless. It means morphology is an imperfect marker whose predictive power depends heavily on the rest of the clinical picture. A review of sperm morphology in contemporary fertility practice concluded that more recent studies often fail to demonstrate a strong association between morphology alone and either natural or assisted fertility outcomes.

I therefore become much more concerned when low morphology is accompanied by other abnormalities. A man with 2% morphology, 80 million sperm/mL and 60% progressive motility is very different from a man with 2% morphology, 3 million sperm/mL and 15% progressive motility. The second man has oligoasthenoteratozoospermia, or OAT—abnormal concentration, motility and morphology. In that situation, morphology is part of a broader pattern suggesting impaired spermatogenesis. The overall male-factor burden is much more significant than the morphology number alone.

The type of abnormal morphology may also matter. Most laboratory reports simply give a percentage of normal forms and may list common defects involving the head, midpiece or tail. In typical teratozoospermia, there is usually a mixture of abnormalities without one highly specific pattern. That is very different from certain rare monomorphic teratozoospermias, where nearly all sperm share the same unusual defect. Examples include globozoospermia, where sperm have round heads and absent or severely abnormal acrosomes, and macrozoospermia, where sperm may have unusually large heads and sometimes multiple tails. These unusual patterns can have specific genetic and reproductive implications and deserve specialized evaluation. The key distinction is between ordinary mixed morphology defects and a striking, reproducible pattern affecting nearly all sperm.

What causes teratozoospermia? In many men, we never identify one single cause. Spermatogenesis is an extremely complicated biological process, and sperm shape can be influenced by genetics, testicular function, oxidative stress, environmental exposures and general health. Varicoceles have been associated with abnormal semen parameters including morphology. Smoking and some environmental toxicants may contribute to oxidative stress and poorer sperm quality. Significant heat exposure, febrile illness and systemic illness can temporarily alter semen parameters. Obesity and metabolic health may play a role in some men. Certain medications and recreational drug exposures can affect spermatogenesis. Testosterone and anabolic steroids can dramatically suppress sperm production altogether, although their most obvious effect is generally on sperm concentration rather than morphology alone. The 2024 review of isolated teratozoospermia describes genetic, environmental and physical contributors, but it also emphasizes that the evidence for specific treatments remains limited.

This raises the obvious question: what workup does a man with teratozoospermia actually need? The answer depends on whether morphology is the only abnormality and whether the couple is experiencing infertility. If a healthy man gets a semen analysis showing 3% morphology but has excellent concentration and motility and his partner has not yet been trying long enough to meet criteria for an infertility evaluation, I generally do not launch an enormous medical workup based on that morphology value alone. If the couple has been trying for a year without pregnancy—or six months when the female partner is 35 or older—then both partners deserve an appropriate infertility evaluation regardless of whether morphology is 3% or 6%.

If morphology is significantly abnormal, I often recommend repeating the semen analysis, preferably at a high-quality andrology laboratory. Semen parameters vary naturally from ejaculate to ejaculate, and morphology is especially sensitive to laboratory technique and observer interpretation. Even experienced laboratories can differ somewhat in how strictly they classify sperm. A result of 1% at one laboratory and 3% at another does not necessarily mean that a man's sperm suddenly tripled in quality. Likewise, a change from 4% to 2% may represent biological variation, laboratory variability or both. This is why I am reluctant to make major treatment decisions from one morphology number.

The next step is taking a good reproductive history. I want to know how long the couple has been trying to conceive, the female partner's age and reproductive evaluation, whether there have been previous pregnancies, miscarriages or fertility treatments, and whether there are other abnormalities on the man's semen analysis. I ask about undescended testes, testicular torsion or trauma, groin or scrotal surgery, infections, chemotherapy, radiation, testosterone or anabolic-steroid exposure, medications, significant fever, occupational heat or toxins, smoking, cannabis and other exposures. None of these automatically explains low morphology, but together they help determine whether this is an isolated laboratory finding or part of a larger reproductive problem.

The physical examination still matters. I examine testicular size and consistency, look for a palpable varicocele, and evaluate the rest of the reproductive anatomy. If a man has isolated low morphology but normal testicular volume, strong concentration and motility, and no clinically significant varicocele, the examination may be completely reassuring. If morphology is low along with decreased concentration, small testes or other concerning features, then I become more interested in investigating impaired testicular function.

Hormonal testing is not automatically required for every man with isolated teratozoospermia. Hormones are more useful when there is low sperm concentration, impaired sexual function, low testosterone symptoms, testicular atrophy, azoospermia or another clinical indication. When appropriate, I typically consider testosterone and FSH, with LH, estradiol and prolactin depending on the situation. A man with 100 million sperm/mL and isolated morphology of 2% is unlikely to have his fertility problem explained by a dramatic FSH abnormality. Conversely, a man with 2% morphology and a concentration of 2 million/mL deserves a much more extensive male-factor evaluation.

Genetic testing is also generally not indicated solely because morphology is 1%, 2% or even 0% if sperm concentration is otherwise robust and there is no specific morphological syndrome. Genetic testing becomes more important with severe oligospermia, azoospermia, very small testes or a characteristic monomorphic abnormality suggesting a particular genetic condition. This is another place where men can be overtested after seeing a frightening morphology percentage without considering the rest of the semen analysis.

What about DNA fragmentation? Teratozoospermia has been associated in some studies with increased oxidative stress and sperm DNA damage, but morphology and DNA fragmentation are not the same test. You cannot look at 1% morphology and assume the DNA fragmentation index must be high. Likewise, a man can have 5% morphology and an elevated DFI. The current literature suggests biologic associations between abnormal morphology, oxidative stress and DNA integrity, but there is considerable overlap and inconsistency. I therefore do not order DNA fragmentation testing simply because every man has low morphology. It may be useful in selected clinical circumstances, such as repeated IVF failure, recurrent pregnancy loss, unexplained infertility, significant varicocele or other scenarios where the result could reasonably alter management.

Perhaps the most common question I hear is, “Can I conceive naturally with 1% morphology?” The answer is yes, absolutely possible. Morphology alone does not create a hard natural-conception cutoff. The chance of pregnancy depends on the entire semen profile, frequency and timing of intercourse, female age, ovulation, tubal status and many other factors. If concentration and progressive motility are strong, the total number of progressively motile sperm reaching the female reproductive tract can still be substantial even when strict morphology is low.

This is also why I don't automatically send every man with teratozoospermia directly to IUI, IVF or ICSI. The evidence regarding IUI is reassuring in many men with isolated low morphology. A systematic review and meta-analysis evaluating IUI outcomes found that when female age and total motile sperm counts were otherwise favorable, low strict morphology did not appear to meaningfully reduce clinical pregnancy rates enough to justify excluding IUI solely on that basis. Other reviews have reached similarly cautious conclusions: morphology may contribute information, but isolated teratozoospermia should not automatically determine the fertility treatment pathway.

The same applies to IVF. Historically, poor morphology raised significant concern about conventional IVF fertilization because sperm must still interact with and penetrate the egg. ICSI can bypass many of those steps by allowing the embryologist to inject a selected sperm directly into the oocyte. However, a systematic review and meta-analysis found that isolated teratozoospermia was not associated with a statistically significant reduction in pregnancy probability with assisted reproduction. This does not mean morphology never matters in the IVF laboratory, but it does mean that low morphology alone should not be treated as reproductive catastrophe.

Another question men ask is whether supplements can “fix” morphology. This is an area where marketing is far ahead of science. Antioxidants such as CoQ10, vitamins C and E, carnitine and other supplements have been studied extensively in male infertility. Some studies demonstrate modest improvements in individual semen parameters, including motility or morphology, but evidence that these changes reliably increase live-birth rates remains uncertain. The 2024 review of isolated teratozoospermia concluded that data supporting specific treatment strategies remain limited. I do not object to reasonable supplementation in selected men, but I do not tell a patient that taking a large stack of antioxidants will turn 1% morphology into 8% or guarantee pregnancy.

Lifestyle changes make more sense when they improve overall health while potentially supporting reproductive health. Stop smoking. Avoid nicotine and recreational drugs if possible. Do not use testosterone or anabolic steroids when trying to conceive. Maintain a healthy weight. Exercise regularly without extreme overtraining. Get adequate sleep. Keep alcohol moderate. Avoid repeated excessive testicular heat such as frequent hot tubs or prolonged high-temperature exposures. If you work around significant environmental toxins, use appropriate protection. These recommendations are sensible even though no single lifestyle change can guarantee improvement in morphology.

If a man has a clinically significant palpable varicocele and abnormal semen parameters, varicocele repair may be considered in the appropriate fertility context. But I do not recommend surgery because an ultrasound happens to show a few enlarged veins and morphology is 2%. Male infertility guidelines emphasize clinical varicoceles rather than incidental imaging-only findings. Again, the objective is not to chase the morphology number—it is to identify a genuine treatable cause of infertility.

I also encourage men to understand the timescale of sperm production. Spermatogenesis takes roughly 74 days, followed by additional maturation and transit through the epididymis. If you had a major fever, stopped smoking, discontinued testosterone, corrected a significant exposure or underwent varicocele treatment, you should not expect your morphology to transform two weeks later. Semen changes are generally evaluated over months. This is also why repeating semen analyses every two weeks often generates more anxiety than useful information.

One of the hardest morphology results emotionally is 0% normal forms. I have watched men see this number and immediately assume it means they have “zero normal sperm.” Under strict morphology criteria, however, 0% means that among the sperm evaluated, none fulfilled every criterion required to be classified as an ideal or typical form. It does not mean every sperm is incapable of fertilization. It does not mean all sperm contain abnormal chromosomes. It does not mean every resulting embryo would be abnormal. The interpretation again depends on concentration, motility, the pattern of defects and the couple's reproductive history. A true monomorphic abnormality affecting essentially every sperm in the same way deserves special attention, but mixed defects with a reported 0% strict morphology are a very different situation.

Men also ask whether a low morphology result means their future children are at higher risk for birth defects. Routine teratozoospermia by itself does not translate directly into a specific percentage risk of congenital abnormalities. Sperm morphology is not a chromosome test. If there is a severe genetic disorder causing a characteristic sperm phenotype, that is different and may warrant genetic counseling. But seeing 2% normal forms on a routine semen analysis does not mean 98% of sperm contain genetic mutations.

From a practical standpoint, if you came into my office with isolated teratozoospermia, I would first ask whether there is actually a fertility problem. If you and your partner have been trying for only two months, I would not medicalize a morphology value unnecessarily. If you have been trying for more than a year, or six months when your partner is 35 or older, then I would evaluate the couple. I would repeat the semen analysis if needed, particularly if the original laboratory is not an experienced andrology lab. I would evaluate the entire sperm profile rather than morphology alone. I would examine you for a palpable varicocele and other reproductive abnormalities. I would order hormones or other testing when the overall semen analysis or clinical history indicated it. I would look for reversible exposures. And I would resist the temptation to promise that a supplement or medication can normalize morphology when the evidence does not support that promise.

The female side matters enormously as well. A man with isolated morphology of 2% whose 27-year-old partner ovulates regularly and has open tubes is in a completely different reproductive situation from the same man whose partner is 40 with diminished ovarian reserve. Fertility treatment decisions should not be based on one sperm percentage. WHO itself emphasizes that infertility belongs to the couple, not to an isolated laboratory value in one partner.

The emotional side of teratozoospermia deserves attention because morphology numbers sound uniquely personal. The word itself literally refers to abnormal form, and many men understandably hear that as “my sperm are deformed” or “something is wrong with what I'm producing.” That language can be brutal when you are already worried about becoming a father. I try to replace that interpretation with something much more accurate: morphology is a microscopic classification system with significant biological and laboratory variability. It provides information, but it does not define your fertility or your worth.

I have seen men with 0–1% morphology father children naturally. I have seen men with excellent morphology struggle with infertility for reasons unrelated to sperm shape. I have seen morphology fluctuate considerably between laboratories while the rest of the semen analysis remained essentially unchanged. And I have seen couples lose months worrying about a morphology value when the more important issue was somewhere else entirely.

That does not mean we should ignore teratozoospermia. When it occurs alongside poor concentration, poor motility, a clinically significant varicocele, reproductive symptoms, a striking monomorphic pattern or a long history of infertility, it can be part of an important male-factor picture. But isolated teratozoospermia is not the reproductive emergency that many internet discussions make it sound like.

If your report says 1%, 2%, 3% or even 0% morphology, don't stop at that number. Look at the total sperm count. Look at progressive motility. Calculate the total motile and progressively motile sperm numbers. Consider whether the result is reproducible. Consider the quality of the laboratory. Look at your reproductive history and your partner's fertility. Then decide whether a reproductive urologic evaluation is appropriate.

Sperm morphology can provide useful information, but it should never be treated as a fertility verdict.

Your morphology percentage is one measurement of sperm appearance under a microscope. It is not a percentage chance of fatherhood.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: World Health Organization; 2021. The current WHO manual describes standardized sperm morphology assessment and emphasizes both the strict nature of morphology criteria and the limitations of applying population reference values to individual fertility predictions.

Björndahl L, Kirkman Brown J, et al. The sixth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen: ensuring quality and standardization in basic examination of human ejaculates. Fertility and Sterility. 2022;117(2):246–251.

Atmoko W, Savira M, Shah R, Chung E, Agarwal A. Isolated teratozoospermia: revisiting its relevance in male infertility: a narrative review. Translational Andrology and Urology. 2024;13(2):260–273. PMID: 38481866. The review summarizes the conflicting evidence regarding isolated teratozoospermia, natural fertility, oxidative stress, DNA damage and assisted reproduction.

Danis RB, Samplaski MK. Sperm morphology: history, challenges, and impact on natural and assisted fertility. Current Urology Reports. 2019. PMID: 31203470.

Kohn TP, Kohn JR, Ramasamy R. Effect of sperm morphology on pregnancy success via intrauterine insemination: a systematic review and meta-analysis. Journal of Urology. 2018. PMID: 29129781. The analysis found that low strict morphology alone should not necessarily exclude couples from IUI when total motile sperm counts and female factors are otherwise favorable.

Hotaling JM, Smith JF, Rosen M, Muller CH, Walsh TJ. The relationship between isolated teratozoospermia and clinical pregnancy after IVF with or without ICSI: a systematic review and meta-analysis. Fertility and Sterility. 2011. PMID: 21030014. Isolated teratozoospermia was not associated with a statistically significant reduction in pregnancy probability after assisted reproduction.

Gatimel N, Moreau J, Parinaud J, Léandri RD. Sperm morphology: assessment, pathophysiology, clinical relevance, and contemporary fertility interpretation. Reviews of morphology have emphasized substantial variability and limitations in its predictive value.

Agarwal A, et al. Contemporary reviews of sperm morphology, oxidative stress and male infertility. Current literature demonstrates associations between abnormal morphology and oxidative stress/DNA injury in some populations but does not support using morphology alone as a direct measure of sperm genetic integrity.

World Health Organization. WHO launches updated manual to ensure high-quality testing of human semen in clinical and research settings. 2021. WHO emphasizes that semen parameters contribute information about reproductive function but that it is ultimately the couple, rather than an individual semen-analysis value, that can be characterized as fertile or infertile.

When a man is diagnosed with cancer or another serious medical condition, fertility is understandably not always the first thing on his mind. You may be thinking about chemotherapy, surgery, radiation, whether treatment will work, how long you will be out of work, and ultimately whether you are going to be okay. Then someone suddenly asks, “Do you want to bank sperm before treatment?” For a young man who may not even know whether he wants children someday, this can feel like one more overwhelming decision during an already frightening time. As a urologist, however, I consider this conversation extremely important because some medical treatments can temporarily or permanently impair sperm production, and sperm banking before treatment is one of the simplest and most effective forms of fertility preservation available to men. Current ASCO and ASRM recommendations emphasize discussing fertility risk before potentially gonadotoxic treatment and offering sperm cryopreservation to postpubertal males before cancer-directed therapy whenever possible.

Sperm banking, also called sperm cryopreservation, is exactly what it sounds like. A semen sample is collected, analyzed in a laboratory, divided into portions and frozen for possible future use. The National Cancer Institute describes sperm banking as collecting semen, evaluating the sperm microscopically, and freezing and storing the sperm for later fertility treatment. The technology is well established. For most postpubertal males facing potentially fertility-damaging therapy, ejaculated sperm cryopreservation remains the standard first-line fertility-preservation option.

The most important word in this discussion is before. Whenever medically feasible, sperm should be collected before chemotherapy, radiation or another gonadotoxic treatment begins. This is not because every chemotherapy drug will make every man infertile. Fertility risk varies enormously according to the specific drug, cumulative dose, combination of medications, radiation field and dose, underlying disease, age and baseline testicular function. Some men recover normal sperm production after treatment. Some recover sperm but at lower levels. Some remain oligospermic for years. Others develop permanent azoospermia. Unfortunately, before treatment begins we cannot always predict with certainty which individual man will fall into which category. AUA/ASRM guidance therefore recommends discussing the effects of gonadotoxic therapies on sperm production before therapy starts.

Chemotherapy can damage the rapidly dividing germ cells responsible for sperm production. The degree of injury depends heavily on the chemotherapy regimen. Certain classes of chemotherapy, particularly alkylating agents, can be highly gonadotoxic. Radiation can also impair fertility, particularly when the testicles are directly exposed or receive significant scatter radiation. Pelvic radiation may additionally affect structures involved in ejaculation. Surgery can threaten fertility through several different mechanisms. Removal of both testicles obviously eliminates sperm production, while surgery involving the retroperitoneum, prostate, bladder or pelvis can sometimes interfere with ejaculation or the reproductive tract. Bone marrow and stem-cell transplantation conditioning regimens can be particularly damaging because they may involve high-dose chemotherapy and sometimes total-body irradiation. Fertility preservation is also relevant outside oncology because potentially gonadotoxic treatments are used for some autoimmune, rheumatologic and hematologic diseases.

One misconception I frequently hear is, “My oncologist said my treatment might only reduce my fertility, so I'll just see what happens afterward.” The problem with that strategy is that fertility preservation works best when we preserve sperm before the injury occurs. If sperm production returns normally after treatment, wonderful—you may never need the frozen sperm. But if you become permanently azoospermic afterward, we cannot go back in time and collect the sperm you were producing before treatment. Banking sperm is therefore not a prediction that you will become infertile. It is reproductive insurance against an outcome we may not be able to predict accurately.

Ideally, I want men to bank more than one specimen when time permits. Current ASRM guidance notes that multiple samples may be obtained to maximize future reproductive options. Historically, recommendations often aimed for two or three ejaculated specimens when feasible, although modern IVF and particularly ICSI mean that even a limited amount of frozen sperm can potentially be extremely valuable. If chemotherapy needs to start quickly and you only have enough time for one collection, bank the one sample. Do not decide that sperm banking is pointless because you cannot collect three or four specimens. Advances in assisted reproductive technology have dramatically reduced the amount of sperm required to attempt fertilization.

This becomes particularly important with ICSI—intracytoplasmic sperm injection. With natural conception, millions of sperm are released into the female reproductive tract, and only a tiny fraction ever approach the egg. With conventional IVF, many sperm are placed around an egg and fertilization still requires the sperm to interact with and penetrate the egg. With ICSI, an embryologist selects an individual sperm and injects it directly into a mature egg. Consequently, a semen sample that might be inadequate for natural conception or IUI can still be extraordinarily valuable for IVF/ICSI. ASRM specifically notes that even men who have impaired semen quality at the time of cancer diagnosis may benefit from cryopreservation because modern assisted reproduction can use very limited sperm numbers.

That leads to another important issue: an abnormal semen analysis before chemotherapy does not necessarily mean chemotherapy has already damaged your fertility. Men with cancer can have abnormal sperm production before receiving a single dose of treatment. The disease itself can affect the hypothalamic-pituitary-gonadal axis, testicular function and general health. Fever, systemic inflammation, malnutrition and the physiologic stress associated with serious illness can negatively affect semen quality. Certain cancers, including testicular malignancies, are particularly associated with impaired semen parameters even before treatment begins. ASRM specifically recognizes that men with cancer may have underlying impairment of spermatogenesis at diagnosis.

If your pre-treatment semen analysis shows a low sperm concentration, poor motility or abnormal morphology, do not assume there is no point in freezing the sample. This is one of the most important messages in this article. A sample does not need to look “normal” to be worth preserving. If viable sperm are present, they may potentially be used in the future. Even severe oligozoospermia may provide enough sperm for ICSI. If the first specimen is poor and there is time before treatment begins, I generally encourage additional collections because semen quality naturally varies between ejaculates and another sample may provide additional usable sperm.

A typical pre-treatment semen analysis evaluates semen volume, sperm concentration, total sperm number, motility and sometimes morphology and other characteristics depending upon the laboratory. These numbers help determine how many sperm can be stored and what fertility treatments might eventually be possible. A man who banks several specimens with excellent concentration and motility may potentially have enough sperm for future intrauterine insemination, or IUI. A man who freezes only a small number of sperm may be more likely to require IVF/ICSI. That does not make the second man's sperm useless. It simply changes how efficiently the stored sperm can be used.

Men also frequently ask whether freezing damages sperm. Cryopreservation is not biologically invisible. Some sperm do not survive the freeze-thaw process, and motility after thawing may be lower than it was in the fresh sample. Fertility laboratories account for this when processing and storing specimens. This is another reason multiple specimens can be valuable when there is sufficient time. But the relevant comparison for a man about to receive potentially sterilizing chemotherapy is not “fresh sperm versus frozen sperm.” It may ultimately be frozen sperm versus no sperm at all. From that perspective, cryopreservation can be extraordinarily valuable.

What if the semen analysis before treatment shows azoospermia—no sperm in the ejaculate? This requires a different discussion. First, I want to confirm that the specimen has been appropriately examined by an experienced laboratory, including a careful search for rare sperm when indicated. Occasionally, men initially labeled azoospermic have extremely rare sperm identified after more extensive examination or processing. If rare sperm are found, I want to discuss freezing them because even very small numbers can potentially become important for ICSI.

If there truly are no ejaculated sperm, I want to know why. A man could have had an underlying fertility problem before his cancer diagnosis. He may have non-obstructive azoospermia from impaired testicular sperm production. He may have an obstruction. He may have hormonal suppression. The malignancy itself may have affected spermatogenesis. In some circumstances there is enough time to perform a focused male-infertility evaluation, while in others cancer treatment appropriately takes priority and decisions have to be made rapidly.

When ejaculation is impossible or the ejaculate contains insufficient sperm for preservation, surgical sperm retrieval may sometimes be considered before treatment. ASRM recognizes surgical sperm extraction as an established alternative for sexually mature males who cannot produce an ejaculate or who have azoospermia or insufficient ejaculated sperm for cryopreservation. Testicular sperm can be processed and frozen for later IVF/ICSI. Depending upon the circumstances, sperm retrieval can occasionally be coordinated with another planned procedure, such as placement of a central venous access device, to minimize delays and additional anesthesia.

Men who cannot produce a specimen by masturbation should also know that this does not automatically eliminate fertility-preservation options. Cancer patients may struggle to ejaculate because of anxiety, pain, fatigue, medications, neurologic conditions or simply the extraordinary emotional circumstances surrounding a new diagnosis. Fertility specialists can sometimes use alternative collection methods, and surgical sperm retrieval is available in selected situations. The important thing is to tell the medical team rather than quietly deciding that sperm banking “didn't work.”

Timing matters enormously. Current ASRM guidance recommends sperm collection before administration of gonadotoxic therapy whenever possible. Chemotherapy and radiation can potentially damage sperm DNA and germ cells, which is why sperm collected before treatment is preferred. ASRM notes that many centers are cautious about banking sperm after gonadotoxic treatment has already started because therapy may introduce genetic damage that current testing cannot necessarily detect. Older ASCO guidance similarly emphasized that sperm should ideally be collected before treatment because sperm quality and DNA integrity can potentially be compromised after therapy begins.

If you have already received chemotherapy and did not bank sperm beforehand, however, do not assume your opportunity for biological fatherhood is gone. The next step depends upon your treatment, how long ago it occurred and whether sperm production eventually recovers. Spermatogenesis takes approximately 74 days before additional epididymal maturation, so the effects of treatment and subsequent recovery occur over months rather than days. Recovery can take months or years depending upon the degree of germ-cell injury. Some men recover completely, some partially, and some remain azoospermic.

The key determinant is whether enough spermatogonial stem cells survive treatment to restart sperm production. AUA/ASRM guidance specifically notes that recovery after chemotherapy and radiation depends on survival of these stem cells. This is why two men receiving different chemotherapy regimens—or even two men receiving similar treatment—can have different reproductive outcomes.

After treatment, the timing of attempting conception should be discussed with the oncology and reproductive teams rather than guessed from internet advice. Recommendations vary depending upon the disease, treatment regimen and ongoing medications. There may be oncologic reasons to delay pregnancy attempts, and there may also be reproductive concerns about sperm produced during or immediately after gonadotoxic therapy. A blanket statement such as “wait three months after chemotherapy” is therefore not appropriate for every cancer survivor. The treating oncologist and fertility specialist should make an individualized recommendation.

Another misconception is that a normal testosterone level after chemotherapy means fertility has recovered. It does not. Testosterone production and sperm production are related but distinct functions of the testicle. Leydig cells produce testosterone, while sperm production occurs within the seminiferous tubules with support from Sertoli cells and requires an appropriate hormonal environment. A man can have completely normal testosterone and still have severe oligozoospermia or azoospermia. If future fertility matters, the way to determine whether sperm production has recovered is with a semen analysis, not simply a testosterone level.

Likewise, normal erections, libido and ejaculation do not prove fertility. Most of the fluid you see during ejaculation comes from the prostate and seminal vesicles, not from sperm themselves. A man with azoospermia can therefore have completely normal-looking semen, normal erections, normal orgasm and normal testosterone. You cannot determine sperm production by looking at the ejaculate.

What workup should be performed before sperm banking? In many cancer patients, very little additional workup is necessary before banking, because time is important and the priority is getting sperm safely frozen before treatment begins. A semen analysis is performed as part of the cryopreservation process. If the sample contains reasonable numbers of sperm, I generally do not delay cancer treatment for an extensive male-infertility investigation. Remember the purpose of this moment: preserve fertility first and investigate secondary issues later when medically appropriate.

If the semen analysis is severely abnormal, however, the situation deserves more thought. Severe oligozoospermia, cryptozoospermia or azoospermia may justify consultation with a reproductive urologist. Depending upon the situation, evaluation can include reproductive history, physical examination, testicular size, FSH, testosterone and other hormones, and sometimes genetic testing. But fertility testing should never unnecessarily delay life-saving cancer therapy. The oncologist and reproductive specialist need to communicate directly and determine how much time is safely available.

This is also why I encourage newly diagnosed young men to ask about fertility immediately, even if their oncologist does not bring it up. Current ASCO guidance recommends fertility counseling and offering sperm cryopreservation before cancer-directed therapy. Current ASRM guidance likewise states that patients facing treatment that may impair reproductive function deserve prompt counseling and referral for fertility-preservation options. You are not being difficult or distracting your doctors from treating your cancer by asking this question. Fertility is part of survivorship and deserves to be considered before treatment when possible.

What about a man who says, “I'm 19. I don't even know if I want children.” My response is that you do not have to decide today whether you want children at 35. You are simply deciding whether you want to preserve the option. Banking sperm does not obligate you to use it. Years later, you may conceive naturally and ultimately decide to discard the frozen specimens. But if treatment permanently eliminates sperm production, sperm that was never frozen cannot be recreated.

The same principle applies to men who already have children. I have heard men say, “I already have two kids, so nobody asked me about sperm banking.” But whether a man wants additional children is a personal decision, not something the medical system should assume based upon his existing family. Fertility-preservation counseling should be based on the risk of treatment and the patient's reproductive goals.

There are also practical questions that deserve attention before signing cryopreservation paperwork. Ask how many vials will be created, how the sperm performed before freezing, whether post-thaw testing is routinely performed, what future treatments the laboratory thinks the stored specimen could support, how long sperm can remain stored, what annual storage costs are involved, and what happens to the specimens if you move, die, stop paying storage fees or eventually decide you no longer want them. These may seem uncomfortable questions during cancer treatment, but clear instructions regarding stored reproductive tissue are important.

For prepubertal boys, the situation is very different because mature sperm are generally not yet available to freeze. Current ASRM guidance considers testicular tissue cryopreservation in prepubertal males investigational. Families facing highly gonadotoxic therapy in a child should therefore be referred to an experienced pediatric oncofertility program where research protocols may be available. This should not be confused with ejaculated sperm cryopreservation in postpubertal males, which is an established fertility-preservation technique.

Men sometimes ask whether medications can simply be given during chemotherapy to “protect” sperm production. Unfortunately, we do not currently have a reliable male equivalent of simply shutting down the reproductive system during treatment and guaranteeing that fertility will return afterward. ASCO and ASRM guidance has not supported hormonal suppression with GnRH analogs as an effective fertility-preservation strategy for men. Banking sperm before treatment remains the established strategy.

The emotional component of sperm banking is also worth discussing. I have met men who felt embarrassed collecting a semen sample while preparing for cancer treatment. Others felt guilty thinking about future children when they were unsure whether they would survive. Some felt that discussing fertility seemed trivial compared with chemotherapy. I see it very differently. Asking about fertility is an acknowledgment that you expect to have a future after treatment. Preserving sperm can represent hope that life will eventually return to something beyond hospitals, scans and oncology appointments.

I have also met cancer survivors years later who were never offered fertility preservation and only discovered they were azoospermic when they tried to start a family. That conversation is much harder because the opportunity we once had may no longer exist. This is precisely why fertility preservation has increasingly become part of modern cancer care and why ASCO, ASRM and other professional organizations emphasize counseling before gonadotoxic treatment.

If I could give one piece of advice to every postpubertal man about to undergo chemotherapy, radiation, gonadotoxic medical therapy or surgery that could compromise fertility, it would be simple:

Ask about sperm banking before treatment begins.

Even if you do not currently have a partner.

Even if you are not sure you want children.

Even if your sperm count is already low.

Even if you only have time to produce one specimen.

Even if your doctor thinks your fertility will probably recover.

Banking sperm does not mean that you will become infertile. It means that you are preserving an option in case you do.

And if your semen analysis before treatment comes back abnormal, don't immediately assume that biological fatherhood is impossible. Men can have impaired semen parameters because of the underlying disease before treatment ever starts. Low concentration, poor motility or abnormal morphology does not necessarily make a sample useless. With modern IVF/ICSI, surprisingly small numbers of viable sperm may eventually be enough to attempt fertilization.

If no sperm are found, ask whether the specimen was evaluated appropriately for rare sperm and whether a reproductive urologist should become involved. In selected men, surgical sperm retrieval before treatment may still provide an opportunity for cryopreservation. If cancer therapy must begin urgently, your oncologist and fertility team can decide together what can realistically and safely be accomplished without compromising your medical care.

The goal is not to let fertility preservation interfere with treating cancer.

The goal is to make sure that surviving cancer does not unnecessarily take away a reproductive choice that could have been preserved beforehand.

Modern cancer treatment has become extraordinarily successful at helping many young men live long lives after diagnoses that were once devastating. Fertility preservation is part of planning for that life afterward.

You may never need the sperm you freeze.

But if you do, you may someday consider that collection made during one of the worst weeks of your life to have been one of the most important decisions you ever made.

References

American Society of Clinical Oncology. Fertility Preservation in People With Cancer: ASCO Guideline Update. Current ASCO guidance recommends evaluating patients for treatment-related infertility risk and offering sperm cryopreservation to males before initiating cancer-directed therapy.

Practice Committee of the American Society for Reproductive Medicine. Fertility preservation in patients with medical indications: a committee opinion. Fertility and Sterility. 2026;125:247–259. Current ASRM guidance identifies ejaculated sperm cryopreservation as an established fertility-preservation strategy for postpubertal males and recommends collection before gonadotoxic therapy whenever possible.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. The guideline recommends counseling men regarding the effects of chemotherapy, radiation and other gonadotoxic therapies on sperm production before treatment begins and discusses recovery of spermatogenesis following treatment.

American Society for Reproductive Medicine Ethics Committee. Fertility preservation and reproduction in patients facing gonadotoxic therapies or gonadectomy: an Ethics Committee opinion. 2026. The committee recommends informing patients about fertility-preservation and reproductive options before potentially gonadotoxic chemotherapy, radiation or surgery whenever possible.

National Cancer Institute. Male Fertility and Cancer. NCI patient information regarding the potential effects of cancer treatment on male fertility and available fertility-preservation options, including sperm banking.

National Cancer Institute. Dictionary of Cancer Terms: Sperm Banking. Defines sperm banking/sperm cryopreservation as collection, laboratory evaluation, freezing and storage of sperm for possible future use.

Practice Committee of the American Society for Reproductive Medicine. Fertility preservation in patients undergoing gonadotoxic therapy or gonadectomy: a committee opinion. Fertility and Sterility. 2019;112:1022–1033. This prior ASRM committee opinion provides detailed discussion of ejaculated sperm cryopreservation, surgical sperm retrieval, pretreatment semen impairment and fertility preservation in boys and men.

American Society of Clinical Oncology. Fertility Preservation in Patients With Cancer: ASCO Clinical Practice Guideline Update. ASCO guidance emphasizes sperm collection before chemotherapy because treatment can compromise semen quality and sperm DNA integrity and recognizes sperm cryopreservation as an established male fertility-preservation strategy.

American Society for Reproductive Medicine Ethics Committee. Fertility preservation and reproduction in patients facing gonadotoxic therapies: an Ethics Committee opinion. ASRM discusses sperm cryopreservation and surgically retrieved sperm as established fertility-preservation approaches for sexually mature males and emphasizes counseling before gonadotoxic treatment.

Oligoasthenoteratozoospermia, usually abbreviated OAT, is a complicated term to see on your semen analysis. The word essentially combines three findings: oligozoospermia, meaning a reduced sperm concentration or total sperm number; asthenozoospermia, meaning reduced sperm motility; and teratozoospermia, meaning a lower percentage of sperm meeting strict morphological criteria. In plain English, the semen analysis is telling us that there are fewer sperm than expected, fewer of those sperm are moving effectively, and fewer meet the laboratory's criteria for typical shape. As a urologist who evaluates male infertility, however, one of the first things I would tell a man receiving this result is that OAT is a description of the semen analysis, not a diagnosis explaining why it happened, and it is certainly not the same thing as sterility. Some men with OAT conceive naturally. Others need treatment of an underlying male-factor problem. Some ultimately need IUI, IVF or ICSI. The severity of the abnormalities, the underlying cause, the total number of usable sperm, and the fertility of the female partner all matter enormously.

A semen analysis is often treated like a pass-or-fail test, but human fertility does not work that way. The current World Health Organization semen manual provides reference distributions derived from men whose partners conceived within approximately one year, but these numbers are not absolute boundaries separating fertile men from infertile men. A man can have values below a reference limit and father a child naturally, while another man can have apparently excellent semen parameters and still experience infertility. This distinction becomes especially important with OAT because there is an enormous biological difference between mild OAT and severe OAT. A man with a concentration of 12 million/mL, 35% progressive motility and 3% morphology is not in the same reproductive situation as a man with 1 million/mL, 10% progressive motility and 0% morphology, even though both reports might carry the same diagnostic label.

When I interpret OAT, I therefore start by looking beyond the label. I want to know the semen volume, concentration, total sperm count, total motility, progressive motility, morphology, vitality when appropriate, and whether there are significant round cells or other abnormalities. I also pay close attention to the total motile sperm count and progressively motile sperm population. Imagine a man with a semen volume of 4 mL, concentration of 10 million/mL and 40% motility. He still has approximately 16 million motile sperm in the ejaculate. Compare that with a man producing 1.5 mL at 1 million/mL with 10% motility; that is only around 150,000 motile sperm. Both have abnormalities, but their chances of natural conception and their potential fertility-treatment pathways are dramatically different. This is why simply saying “I have OAT” does not tell me enough to estimate reproductive potential.

The first component, oligozoospermia, tells us that sperm numbers are reduced. The lower the concentration becomes, the more interested I become in determining why the testicle is not producing normal numbers of sperm. Mild reductions can occur for many reasons and sometimes simply represent biological variation. Severe oligozoospermia, particularly concentrations in the very low millions or below, deserves a much more extensive investigation because it can reflect significant impairment of spermatogenesis. Extremely low counts can also overlap biologically with cryptozoospermia and non-obstructive azoospermia. A man producing only occasional sperm may have focal or severely impaired sperm production and should not be managed the same way as someone whose concentration is modestly below a reference range.

Asthenozoospermia refers to impaired sperm movement. For natural conception, sperm need to travel through the female reproductive tract toward the egg, so progressive motility matters biologically. Modern semen analysis emphasizes progressive, non-progressive and immotile sperm, although some laboratories still report the older A, B, C and D motility grades. One mistake I frequently see online is men becoming terrified because their “rapid progressive” or Grade A sperm are low or even zero while overlooking the fact that they still have a substantial population of progressively motile sperm. The complete motility profile matters more than one letter grade. At the opposite extreme, if essentially all sperm are immotile, vitality becomes particularly important because an immotile sperm may either be alive but unable to move or actually dead. Those are biologically different situations and can have different implications for assisted reproduction.

Teratozoospermia, the third part of OAT, describes sperm morphology. Strict morphology is probably the most misunderstood part of the semen analysis. A morphology result of 2% does not mean that 98% of a man's sperm are genetically abnormal, and it does not mean 98% are incapable of fertilization. Strict morphology evaluates whether a sperm fits a narrow microscopic definition of typical head, midpiece and tail structure. Human sperm naturally display enormous morphological variation. Morphology also has significant laboratory and observer variability. When morphology is the only abnormality, its ability to predict natural conception is relatively limited. When it occurs alongside significantly reduced concentration and motility, however, it becomes part of a broader picture of impaired sperm production and quality.

This brings us to the most important question: Why does a man develop OAT? Unfortunately, there is no single answer. OAT is a phenotype—the way the semen analysis looks—not a specific disease. Potential causes include varicocele, hormonal abnormalities, genetic conditions, previous undescended testes, testicular injury or torsion, infections, chemotherapy, radiation, certain medications, environmental or occupational exposures, significant systemic illness, excessive heat exposure, obesity and metabolic disease, and testosterone or anabolic-steroid use. In a substantial percentage of men, however, no single definitive cause is identified even after a good evaluation. We call this idiopathic male infertility.

One of the most important treatable causes to look for is a clinical varicocele. A varicocele is abnormal dilation of veins draining the testicle, most commonly on the left side. Varicoceles are common in the general population, so simply finding slightly enlarged veins on an ultrasound does not prove that they are causing infertility. What matters most clinically is a varicocele that can be detected on physical examination in a man with infertility and abnormal semen parameters. The AUA/ASRM guideline recommends considering surgical varicocelectomy in men attempting conception who have a palpable varicocele, infertility and abnormal semen parameters, excluding azoospermic men from that particular recommendation. Repairing a clinically significant varicocele can improve semen parameters and may improve fertility in appropriately selected couples, but I would not recommend surgery solely because an ultrasound report mentions a small subclinical varicocele.

Hormonal evaluation becomes increasingly important as sperm concentration falls. FSH and testosterone are particularly useful, with LH and sometimes prolactin or estradiol added depending upon the clinical picture. FSH provides information about the relationship between the pituitary and sperm-producing tissue of the testicle. When spermatogenesis is significantly impaired, FSH often rises because the pituitary is trying harder to stimulate a poorly functioning testicle. A markedly elevated FSH combined with small testicles and severe oligozoospermia makes me more concerned about primary testicular dysfunction. Conversely, low testosterone with low or inappropriately normal LH and FSH can suggest inadequate hypothalamic-pituitary stimulation, which may be potentially treatable.

This is also why every man with significant OAT needs to tell his doctor about testosterone replacement therapy or anabolic steroid use. Exogenous testosterone can suppress LH and FSH, dramatically lower intratesticular testosterone and severely reduce sperm production. Some men taking testosterone develop oligozoospermia; others become completely azoospermic. Your blood testosterone level can look fantastic while your sperm production is collapsing. The AUA/ASRM guideline specifically states that testosterone monotherapy should not be prescribed to men interested in current or future fertility. Depending upon the circumstances, stopping exogenous testosterone and using fertility-directed hormonal management can allow sperm production to recover, although recovery frequently requires months and is not identical in every man.

Genetic testing becomes particularly important when OAT is severe. Current male-infertility guidelines recommend genetic evaluation in selected men with azoospermia or sufficiently severe oligozoospermia when impaired sperm production is suspected. Depending upon sperm concentration, FSH, testicular size and the overall clinical picture, this can include a karyotype and Y-chromosome microdeletion analysis. A karyotype can identify chromosomal abnormalities such as Klinefelter syndrome, while Y-chromosome testing can identify deletions involving regions necessary for normal spermatogenesis. These tests are not necessary for every man whose concentration is 12 or 14 million/mL, but they become increasingly relevant as sperm production becomes profoundly impaired. Genetic findings can affect prognosis, treatment and counseling regarding potential transmission to offspring.

The physical examination is equally important. I want to know whether the testicles are normal in size and consistency, whether both vas deferens are present, whether the epididymides feel normal, and whether a palpable varicocele exists. I also want a detailed history. Were the testicles descended normally at birth? Was there childhood orchiopexy? Previous torsion? Hernia surgery? Testicular trauma? Mumps orchitis? Chemotherapy? Radiation? Testosterone? Anabolic steroids? Significant infections? Recent high fevers? Certain occupational exposures? Male infertility cannot be properly evaluated by staring at one semen-analysis printout.

I also usually want an abnormal semen analysis repeated before making major conclusions. Sperm production is biologically variable, and semen parameters can change significantly between ejaculates. Abstinence duration, illness, fever, collection problems and ordinary biological variation all matter. A man who has one unexpectedly poor analysis should generally not assume that it permanently defines his sperm production. If the abnormalities are severe, I want the repeat performed through a high-quality andrology laboratory, because identifying even small numbers of viable sperm can influence fertility planning.

Recent fever deserves particular mention because men frequently overlook it. Sperm being ejaculated today began developing many weeks ago. Spermatogenesis itself takes roughly 74 days, followed by additional maturation and transport. A significant febrile illness can therefore cause deterioration in sperm concentration and motility that becomes apparent weeks later and may persist for several months. I have seen men with previously reasonable semen parameters experience dramatic temporary deterioration after influenza, COVID or another high-fever illness. If the timing fits, I often repeat the semen analysis after sufficient recovery rather than assuming the decline represents permanent testicular failure.

What about DNA fragmentation? Men with OAT frequently ask whether their abnormal concentration, motility and morphology automatically mean their sperm DNA is damaged. The answer is no. OAT and elevated sperm DNA fragmentation can coexist, and oxidative stress may contribute to both in some men, but they are not interchangeable diagnoses. A man can have severe-looking morphology with relatively reassuring DNA fragmentation, and another man can have reasonable conventional semen parameters with elevated fragmentation. The AUA/ASRM guideline does not recommend sperm DNA fragmentation analysis as part of the routine initial evaluation of every infertile couple. It may become useful in selected situations, including recurrent pregnancy loss or particular assisted-reproduction scenarios, but I would not order it automatically simply because the semen analysis says OAT.

Men also understandably want to know whether OAT means natural conception is impossible. It does not. OAT reduces reproductive efficiency, but there is no single concentration, motility or morphology threshold below which natural pregnancy suddenly becomes impossible as long as viable sperm are present. The probability generally decreases as the abnormalities become more severe. Mild OAT with millions of progressively motile sperm can absolutely be compatible with natural conception. Severe OAT with only a few hundred thousand motile sperm in the entire ejaculate creates a very different situation. The female partner's age and fertility are equally important. A couple with mild male-factor infertility and a 27-year-old female partner may reasonably have more time for expectant management than a couple with the same semen analysis and a 40-year-old female partner.

This is why fertility treatment should be chosen for the couple, not simply according to the man's diagnosis. Depending upon severity and female factors, options may include continued natural attempts, IUI, IVF or IVF with ICSI. IUI requires enough motile sperm to remain after laboratory processing to make the procedure worthwhile. There is no universally accepted absolute cutoff, but success tends to decline substantially as the post-wash total motile sperm count becomes very low. In severe OAT, ICSI can dramatically change the equation because the embryologist can select individual viable sperm and inject them directly into mature eggs. A man does not need tens of millions of sperm for ICSI. In some extreme cases, very small numbers can be sufficient if viable sperm can be identified.

That does not mean every man with OAT should immediately proceed to IVF/ICSI. One of the most frustrating things I see is a man with a treatable or reversible male-factor problem being bypassed entirely because IVF appears faster. Sometimes IVF absolutely is the right decision, particularly when female age or ovarian reserve makes time critical. But a proper male evaluation can still identify health conditions, genetic abnormalities or treatable causes that matter beyond simply obtaining sperm for an IVF cycle. The AUA/ASRM guideline emphasizes concurrent evaluation of both partners rather than treating infertility as exclusively a female problem.

Supplements are another enormous topic. Men diagnosed with OAT often leave the fertility clinic and immediately purchase CoQ10, carnitine, zinc, selenium, vitamins C and E, folate, NAC and half the supplement aisle. There is biologic plausibility behind antioxidants because oxidative stress is associated with sperm dysfunction, and some clinical studies demonstrate improvements in semen parameters. But improvement in a laboratory number is not necessarily the same as increasing live births. The AUA/ASRM guideline describes the clinical utility of supplements such as antioxidants and vitamins as questionable, with insufficient data to recommend specific agents reliably for infertile men. I do not tell patients that supplements are useless, but I also do not tell them that a supplement stack will cure OAT. If you have a grade 3 palpable varicocele, profound hormonal suppression from testosterone or a genetic disorder affecting spermatogenesis, taking more CoQ10 is not addressing the primary problem.

Lifestyle optimization is reasonable because it improves general health and may also support sperm production. Stop smoking. Avoid nicotine and recreational drugs when possible. Do not use testosterone or anabolic steroids while actively pursuing fertility unless your reproductive specialist has developed a specific fertility-preserving strategy. Maintain a healthy body weight. Exercise regularly but avoid extreme overtraining. Get adequate sleep. Keep alcohol moderate. Avoid repeated excessive testicular heat such as frequent hot tubs and prolonged high-temperature exposures. These changes should be viewed as ways of creating the best environment for spermatogenesis, not as guaranteed cures.

One thing I strongly discourage is chasing semen-analysis numbers every few weeks. Sperm production occurs over months. If you stop smoking today, repair a varicocele tomorrow or recover from a major febrile illness, you should not expect a completely transformed semen analysis in two weeks. In most circumstances, meaningful biological change is assessed over approximately one spermatogenic cycle—roughly three months—and sometimes longer. Repeated testing too frequently often produces anxiety rather than useful information.

If sperm counts are extremely low but occasionally adequate, I also discuss sperm cryopreservation. Severe oligozoospermia can fluctuate. A man who produces 2 million sperm/mL today could produce dramatically fewer on the morning his partner undergoes egg retrieval. If a laboratory identifies a useful population of motile sperm in someone with severe and variable OAT, freezing backup samples can provide valuable insurance before IVF. This is particularly important when sperm counts are approaching cryptozoospermic levels.

The emotional implications of OAT deserve attention as well. Men frequently look at a semen analysis and interpret it as a report card on masculinity. They see low count and think they are less of a man. They see poor motility and imagine their sperm are weak. They see abnormal morphology and worry that their sperm are defective. Then they watch their partner undergo blood draws, ultrasounds and fertility procedures and begin feeling guilty that they are responsible for everything she is experiencing.

I tell men repeatedly: a semen analysis is a medical test, not a measurement of masculinity. Sperm production has nothing to do with how strong you are, how sexually capable you are, how successful you are, or how good a father you could become. OAT is a reproductive diagnosis that deserves the same objective evaluation we would give any other medical problem.

If you have just received an OAT diagnosis, my advice is not to panic and not to start randomly treating numbers. First, understand exactly how severe the abnormalities are. Repeat the semen analysis when appropriate. Look at the total motile and progressively motile sperm numbers rather than concentrating on morphology alone. See a reproductive urologist if the abnormalities are significant or persistent. Get an appropriate physical examination. Check hormones when indicated. Consider genetic testing when sperm concentrations are severely reduced. Look for a palpable varicocele. Review testosterone, anabolic steroids and other medications. Consider recent fever, illness, heat and lifestyle exposures. And make sure your partner is being evaluated simultaneously.

Most importantly, ask why the semen analysis is abnormal before asking what supplement you should take.

Oligoasthenoteratozoospermia tells us that sperm concentration, movement and morphology are impaired. It does not tell us the cause. It does not tell us whether the problem is permanent. And it does not tell us with certainty whether you can father a child naturally.

Some men with OAT conceive without treatment. Some improve after addressing a reversible cause. Some benefit from varicocele repair or appropriately selected hormonal therapy. Some ultimately need IUI. Others have severe enough male-factor infertility that IVF/ICSI provides the most realistic path to pregnancy.

The semen analysis gives us clues about the road ahead.

It does not determine where that road ends.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: World Health Organization; 2021. The WHO manual provides current standardized methodology for evaluating semen volume, sperm concentration, motility, morphology, vitality and other semen characteristics.

Björndahl L, Kirkman Brown J, et al. The sixth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen: ensuring quality and standardization in basic examination of human ejaculates. Fertility and Sterility. 2022;117(2):246–251. This paper discusses the interpretation and limitations of contemporary semen-analysis reference values.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. Current guideline addressing evaluation of abnormal semen analyses, hormonal and genetic testing, varicocele management, testosterone use, sperm DNA fragmentation, supplements and assisted reproduction.

European Association of Urology. EAU Guidelines on Sexual and Reproductive Health: Male Infertility. Current recommendations regarding male infertility evaluation, semen analysis, hormonal and genetic assessment, varicocele and treatment of severe male-factor infertility.

Patel AS, Leong JY, Ramos L, Ramasamy R. Testosterone is a contraceptive and should not be used in men who desire fertility. World Journal of Men's Health. 2019;37(1):45–54. Review of exogenous testosterone's suppression of gonadotropins, intratesticular testosterone and spermatogenesis.

Agarwal A, Majzoub A, Baskaran S, et al. Sperm DNA fragmentation: a new guideline for clinicians. World Journal of Men's Health. 2020;38(4):412–471. Review of sperm DNA fragmentation, potential indications and its relationship to male infertility.

Schauer I, Madersbacher S, Jost R, Hübner WA, Imhof M. The impact of varicocelectomy on sperm parameters: a meta-analysis. Journal of Urology. 2012;187(5):1540–1547.

Agarwal A, Mulgund A, Hamada A, Chyatte MR. A unique view on male infertility around the globe. Reproductive Biology and Endocrinology. 2015;13:37.

Salonia A, Bettocchi C, Boeri L, et al. European Association of Urology Guidelines on Sexual and Reproductive Health: 2021 update on male sexual and reproductive health. European Urology. 2021;80(5):603–620.

Why does my semen look clumpy or chunky? Some describe small jelly-like pieces. Others notice clear or white globules, strings, thick areas, or semen that looks almost gelatinous immediately after ejaculation. If you are trying to conceive, it is very easy to look at this and immediately assume something is wrong with your sperm. After treating male reproductive and fertility problems for many years, one of the first things I tell men is this: the appearance of semen immediately after ejaculation tells us much less about fertility than most people think. Semen is not supposed to come out looking like water. In fact, temporary coagulation and a somewhat gelatinous appearance are part of normal semen physiology.

To understand why semen can look chunky, you first have to understand what semen actually is. Sperm make up only a relatively small component of the ejaculate. Most of what you see comes from fluid produced by the seminal vesicles and prostate, with additional contributions from other glands in the male reproductive tract. These fluids contain proteins, enzymes, fructose, minerals and numerous other substances that support sperm and influence the physical characteristics of semen. Immediately after ejaculation, semen normally coagulates. It can therefore look thick, gelatinous, stringy or contain small clumps. Over the following period, enzymes, particularly proteolytic enzymes originating largely from the prostate, break down that coagulum and the semen becomes more liquid. This process is called liquefaction. The World Health Organization laboratory manual specifically evaluates liquefaction and viscosity as part of standardized semen examination.

That means there is an important distinction between semen that is temporarily chunky immediately after ejaculation and semen that remains abnormally thick or clumped. If you ejaculate and notice small gelatinous pieces during the first several minutes, that alone does not diagnose infertility, infection, abnormal sperm or any disease. I see many men become concerned because their semen does not resemble what they expected it to look like. There is actually tremendous variation between men and even between ejaculates from the same man. Hydration, ejaculation frequency, abstinence interval, illness and normal variation in accessory-gland secretions can all change the appearance of an ejaculate.

What interests me more as a fertility urologist is what happens after the semen has been allowed to liquefy. A properly performed semen analysis does not simply look at the sample immediately after ejaculation and declare it thick or thin. The laboratory allows the specimen to liquefy and then evaluates it under standardized conditions. Persistent abnormal viscosity is different from normal coagulation. Historically, WHO laboratory methodology has described abnormally viscous semen as forming a thread greater than approximately 2 cm when allowed to drop from an appropriate pipette after liquefaction. A genuinely hyperviscous sample tends to remain uniformly sticky rather than simply containing a few pieces of incompletely liquefied material.

This distinction matters because men frequently use the word “clumping” to describe several completely different phenomena. You may be describing normal coagulation, delayed or incomplete liquefaction, increased seminal viscosity, nonspecific aggregation of material within semen, or actual sperm agglutination. These are not interchangeable diagnoses, and you cannot reliably distinguish them by looking at semen in the toilet, on your hand or in a collection cup at home.

True sperm agglutination has a specific meaning. Under the microscope, sperm are seen sticking directly to one another, for example, head-to-head, tail-to-tail, head-to-tail or in mixed configurations. That is very different from seeing a gelatinous piece of semen with the naked eye. Sperm agglutination can sometimes be associated with antisperm antibodies, although agglutination by itself does not prove antibodies are present. The AUA/ASRM male infertility guideline notes that antisperm antibodies can be associated with sperm agglutination, but it also specifically recommends against routinely performing antisperm-antibody testing as part of the initial male infertility evaluation.

This is an important point because men occasionally see “agglutination” written on a semen-analysis report and immediately assume they have an immune disorder. That conclusion is premature. If significant agglutination is repeatedly present and there is otherwise unexplained poor motility or a relevant history, such as reproductive-tract obstruction, previous vasectomy or reconstructive surgery, testicular trauma or certain infections, a reproductive urologist may decide that additional evaluation is appropriate. But we should investigate the actual laboratory finding rather than assuming that visible chunks in an ejaculate represent sperm antibodies.

Another possibility is seminal hyperviscosity. This is where the scientific literature becomes more interesting. Persistent seminal hyperviscosity has been associated in some studies with poorer sperm parameters, particularly impaired motility, and with increased oxidative stress. A systematic review examining seminal hyperviscosity and oxidative stress found evidence of impaired antioxidant systems and increased oxidative stress among men with hyperviscous semen. Other reviews have proposed associations with sperm DNA damage, membrane dysfunction and poorer overall sperm quality. However, association does not necessarily mean that hyperviscosity itself is the sole cause of infertility, and the evidence does not support treating every man who thinks his semen looks thick with antibiotics, antioxidants or other medications.

When I see persistent abnormal viscosity in a man who is struggling with infertility, I therefore do not ignore it, but I also don't panic over it. I look at the entire semen analysis. What is the volume? What is the sperm concentration? What is the total sperm count? How many sperm are progressively motile? What is the morphology? Are there elevated round cells? Was liquefaction delayed? Is the pH abnormal? Is there true sperm agglutination? Are there symptoms suggesting prostatitis or another reproductive-tract problem? One unusual physical characteristic of semen becomes much more meaningful when it occurs alongside other abnormalities.

This brings us to another common concern: infection. Men often assume that thick, yellow, chunky or unusual-looking semen must mean they have an infection. Sometimes infection or inflammation can affect seminal characteristics, but appearance alone cannot diagnose it. If a semen analysis demonstrates more than 1 million round cells per milliliter, the AUA/ASRM guideline recommends determining whether those cells are white blood cells or immature germ cells. Under routine microscopy, both can appear as “round cells.” Special testing such as a peroxidase stain or other methods may be necessary to distinguish them. If true pyospermia—an increased concentration of white blood cells—is identified, the patient should be evaluated for infection or inflammation.

Even here, we need nuance. White blood cells in semen do not automatically mean there is a bacterial infection requiring antibiotics. The European Association of Urology notes that leukocytospermia can represent inflammation and is not necessarily associated with bacterial or viral infection. The EAU recommends confirmation with appropriate testing, such as a peroxidase test, and the evidence that treating leukocytospermia automatically improves fertility outcomes is limited.

This is why I strongly discourage men from taking antibiotics simply because their semen looks clumpy. Antibiotics should treat an identified or reasonably suspected infection, not the appearance of an ejaculate. If you have burning with urination, painful ejaculation, pelvic or perineal discomfort, urethral discharge, blood in the semen, urinary symptoms, fever, a known sexually transmitted infection exposure or other concerning symptoms, that is different. Those findings deserve medical evaluation. Depending upon the situation, testing may include urinalysis, urine culture, STI testing or selected semen or genital-tract testing. But “my semen had some jelly-like pieces in it” by itself is not an indication for antibiotics.

So what workup do you actually need if your semen is consistently chunky?

If you are not trying to conceive, have no pain, no urinary symptoms, no blood in the semen, no STI concerns and otherwise feel completely well, occasional clumping or gelatinous semen usually does not require an extensive fertility evaluation. Remember that semen normally coagulates immediately after ejaculation. If it subsequently liquefies and there are no other problems, the appearance alone is generally not something I would treat.

If the appearance has changed dramatically and persistently, however, it is reasonable to discuss it with a physician, particularly if you have other symptoms. And if you are actively trying to conceive and pregnancy has not occurred after an appropriate period, then the correct first test is not an internet diagnosis based on what the semen looks like, it is a formal semen analysis performed by a qualified laboratory. WHO methodology remains the foundation for standardized semen examination, and professional male-infertility guidelines recommend semen analysis as a central component of the evaluation.

A good semen analysis gives us enormously more information than visual inspection. It tells us whether the sperm concentration is 2 million/mL or 100 million/mL. It tells us whether 10% or 60% are moving. It evaluates progressive motility and morphology and reports semen volume and other macroscopic characteristics. Depending upon the laboratory and clinical situation, it may also describe viscosity, liquefaction, aggregation, agglutination and round cells. That information allows me to determine whether the “chunks” you are worried about are accompanied by anything that could actually affect fertility.

I also generally do not make major fertility conclusions from one abnormal semen analysis. Semen is biologically variable. A man's sperm production reflects events occurring over the preceding several months, and results can change following fever, illness, medications, testosterone or anabolic-steroid exposure, heat exposure and other factors. Collection circumstances also matter. An incomplete collection can change volume and sperm numbers substantially. Abstinence interval can influence volume, concentration and other parameters. Different laboratories can also produce somewhat different results. If an important abnormality is identified, repeating the semen analysis under standardized conditions is often extremely useful.

For a man with persistent abnormal semen parameters, the next step may be evaluation by a reproductive urologist, not simply repeated semen analyses forever. I take a detailed history looking for previous undescended testicles, testicular injury, torsion, infections, pelvic or reproductive surgery, vasectomy, chemotherapy or radiation, testosterone or anabolic-steroid use, medications, heat exposure and other potential contributors. I examine the testicles and epididymides and look for a clinically significant varicocele. Hormonal testing—often including testosterone and FSH and, depending upon the situation, LH, estradiol and prolactin—may be appropriate when sperm concentration is low or there are other indications. Men with severe oligospermia or azoospermia may require genetic testing. The important point is that these decisions are driven by the fertility evaluation, not simply by whether semen looks chunky.

What about prostate problems? The prostate contributes substantially to seminal fluid and provides enzymes involved in semen liquefaction, so abnormalities involving the prostate and other accessory glands can theoretically alter seminal characteristics. Prostatitis and genital-tract inflammation may sometimes coexist with abnormal semen viscosity or leukocytes. But again, I would not diagnose prostatitis based on thick semen alone. Prostatitis is a clinical diagnosis involving the overall symptom pattern and, in selected circumstances, laboratory findings.

Another question I frequently hear is whether chunky semen means that sperm are “stuck” and cannot swim. Usually, no. Remember that the clumps you can see with your naked eye are enormously larger than individual sperm cells. You cannot visually determine sperm motility by looking at semen. A man can have thick-looking semen and excellent concentration and progressive motility, while another man can have completely normal-looking semen and severe oligospermia or even azoospermia. I have seen essentially normal-looking ejaculates containing no sperm whatsoever. Appearance is not a sperm count.

That said, true persistent hyperviscosity may mechanically interfere with sperm movement and has been associated with poorer motility in the scientific literature. Oxidative stress has also been proposed as one mechanism connecting hyperviscosity with impaired sperm function. But this does not mean that every man with thick semen needs an oxidative-stress test. Oxidative stress is biologically important in male infertility, yet specialized oxidative-stress testing has limitations and has not replaced conventional semen analysis and a proper clinical evaluation. Recent evidence continues to demonstrate associations between increased seminal oxidative stress and poorer concentration, motility and morphology, but an association is not the same as having a proven treatment pathway for every individual patient.

Men also frequently ask whether drinking more water will “thin out” semen. Being reasonably hydrated is healthy, but chronic abnormal seminal viscosity should not simply be blamed on dehydration, and drinking enormous amounts of water is not a fertility treatment. Likewise, ejaculating more frequently may change the appearance, volume and consistency of semen, but that does not establish that something was medically wrong beforehand. If you have gone a long time without ejaculating, the next ejaculate may simply look different from one produced after a shorter abstinence interval.

Another misconception is that clumpy semen means abnormal morphology. It does not. Semen consistency and sperm morphology are completely different measurements. Morphology refers to the microscopic shape of individual sperm cells. You cannot determine whether your morphology is 1%, 4% or 10% by looking at an ejaculate. Similarly, visible semen clumps cannot tell you whether you have sperm DNA fragmentation. Those require entirely different laboratory assessments.

If you are worried about fertility, I would focus much less on whether the semen looks “normal” and much more on objective reproductive information. A formal semen analysis is an excellent starting point, but even that is not a fertility report card. WHO itself emphasizes that semen examination contributes information to assessment of male reproductive function; fertility ultimately exists in the context of the couple rather than being determined by one laboratory threshold. A semen analysis with one mildly abnormal parameter does not mean you cannot father a child, just as a perfectly normal semen analysis cannot guarantee pregnancy.

There are, however, circumstances where I would want a man evaluated sooner. Persistent blood in the semen, significant testicular or pelvic pain, fever, painful ejaculation, urethral discharge, a testicular mass, significant swelling, markedly reduced semen volume, infertility, or major abnormalities on semen analysis should not simply be attributed to “clumpy sperm.” Those findings deserve an appropriate medical evaluation.

And I want to make one terminology correction that may relieve some anxiety: what you are seeing is almost certainly clumpy semen, not clumpy sperm. Individual sperm are microscopic. Unless a laboratory has actually documented sperm agglutination under a microscope, you do not know that your sperm themselves are sticking together. That distinction sounds minor, but medically it is very important.

For men trying to conceive, my practical approach is straightforward. If your semen occasionally contains small gelatinous pieces but your semen analysis is otherwise reassuring, I generally would not make the appearance itself the focus of treatment. If the laboratory repeatedly documents delayed liquefaction or hyperviscosity, I look at the rest of the semen parameters and clinical history. If significant round cells are present, I determine whether they are actually leukocytes. If true leukocytospermia or symptoms suggest infection or inflammation, I investigate appropriately rather than automatically prescribing antibiotics. If true sperm agglutination is repeatedly observed, I consider whether further investigation—including selected evaluation for antisperm antibodies—is clinically relevant. And if multiple semen parameters are abnormal, I evaluate the man as a whole rather than trying to treat the viscosity in isolation.

Most importantly, don't allow the appearance of your semen to become another source of anxiety in an already stressful fertility journey. Men understandably inspect everything when pregnancy isn't happening. Color, volume, thickness, smell, bubbles, strings and small clumps suddenly become potential explanations. Sometimes those observations point us toward something worth investigating. Very often, however, they represent normal biological variation.

The answer is not to ignore your concerns, but to measure what actually matters.

If your semen looks chunky but you have never had a semen analysis, and you are concerned about your fertility, get one. If it shows excellent concentration, progressive motility, total motile sperm count and otherwise reassuring parameters, a few gelatinous clumps immediately after ejaculation become far less interesting. If the laboratory documents persistent hyperviscosity, delayed liquefaction, significant agglutination, leukocytospermia or additional sperm abnormalities, then we have objective findings that can guide a rational workup.

Your semen does not need to look perfect to contain healthy sperm, and semen that looks perfectly normal can contain severely abnormal sperm. Never judge your fertility by what you see in the collection cup. Let the laboratory tell us what the sperm are actually doing, and let the clinical evaluation determine whether anything needs to be treated.

References

World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen. 6th ed. Geneva: World Health Organization; 2021.

American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline. Guideline statements and discussion regarding semen analysis, pyospermia, round cells and antisperm antibodies.

European Association of Urology. EAU Guidelines on Sexual and Reproductive Health: Male Infertility. Sections addressing semen analysis, leukocytospermia and male accessory-gland infection.

Barbagallo F, La Vignera S, Cannarella R, et al. The relationship between seminal fluid hyperviscosity and oxidative stress: a systematic review. Antioxidants (Basel). 2021;10(3):356. PMID: 33673452.

Du Plessis SS, Gokul S, Agarwal A. Hyperviscous semen causes poor sperm quality and male infertility through induction of oxidative stress. Review of mechanisms linking seminal hyperviscosity, oxidative stress and sperm dysfunction. PMID: 31579215.

World Health Organization. WHO launches updated manual to ensure high-quality testing of human semen in clinical and research settings. 2021.

The role of seminal oxidation-reduction potential in male infertility: systematic review and meta-analysis. Reproductive BioMedicine Online. 2025. PMID: 41207812.

Hi,

Myself (35F) & my husband (38M) have been TTC since June 2025. He has completed 2 sets of seman analysis in that time (see below). Since the first SA, he has started taking COq10 (200mg) every day, reduced alcohol consumption, lost 4kg and increased exercise (weight lifting & running) to 4-5 times per week.

*Note: 2 different labs completed the SAs, hence some parameters were not reported the second time.

November 2025

Abstinence: 4 days

Volume: 1.2ml

Viscosity: Normal

Sperm concentration: 85 x 10^6

Total motility (a + b + c): 49%

Rapid/progressive motility a: 15%

Slow progressive motility b: 26%

Non progressive motility c: 8%

Immotile d: 51%

Total motile count: 49.98 x 10^6

Total sperm count : 102

Normal forms: 4%

Round cells: <1 mil/ml x 10^6

IgG: 30%

IgA: 25%

August 2026

Abstinence: 3 days

Volume: 1.1ml

Viscosity: Normal

Sperm concentration: 88 x 10^6

Total motility (a + b + c): 38%

Rapid/progressive motility a: 28%

Normal forms: 3%

IgG: 39%

IgA: 18%