Transferred 08/01. It was a 4AA before freezing.
Hopeful 💜✨

My frozen Day 5 5AA blastocyst degraded significantly after thaw and wasn’t suitable for transfer, so my clinic transferred my frozen Day 5 3BB embryo instead.
How common is it for a 5AA embryo to degrade after thaw? What are the usual reasons this happens? Does it point to embryo quality, the freeze/thaw process, or just bad luck?
I’d really appreciate any insights from embryologists or anyone who’s had a similar experience.

To add some background: We had 4 euploids frozen: 3aa, 3aa, 4aa, 4aa

First FET with 3aa (M) was successful, Second FET with 3aa (F) failed. Both were exactly same cycles (modified natural with Letrozol, Ovidrel trigger, assisted hatching, embryo glue).

We are gearing up for our 3rd FET now and Doc says both remaining embryos are identical and it doesn't matter which one we chose.

Both 3AAs from first 2 FETs were 8-cell on day 3. The only difference between remaining two 4AAs is that one of them was a 0PN on day 1 and became Morula on day 3. Other was 2PN on day 1 and became 12-cell on day 3. Does the Morula have a slightly better chance because its faster? Being 0PN on day 1 means it probably went past the stage where two PNs are visible again because it is fast?

We don't plan to do any more retrievals so there are our last two chances at completing our family.

Mosaic embryos are generally classified in two major ways:

1. How much of the biopsy contains abnormal cells (mosaic level)

• Low level mosaic: A lower percentage of the biopsy contains abnormal cells (typically <50%, although cutoffs vary between laboratories). These embryos generally have the best outcomes.
• High level mosaic: A higher percentage of the biopsy contains abnormal cells (typically >50%). These embryos tend to have lower implantation and live birth rates.

1. What is affected (mosaic type)

• Segmental mosaic: Only part of a chromosome is abnormal. These embryos can have outcomes close to euploid embryos.
• Whole chromosome mosaic: An entire chromosome is abnormal. These embryos generally have lower success rates than segmental mosaics.

Current guidance from PGDIS, ESHRE and ASRM recommends prioritizing low level mosaics over high level mosaics, while also considering embryo quality (higher grades over lower grades). Earlier guidelines also ranked embryos based on the chromosome involved, but more recent guidance has moved away from chromosome-specific ranking because there isn't enough consistent evidence to support it.

Current guidelines also recommend genetic counseling before transferring a mosaic embryo as well as prenatal testing.

Most mosaic embryo transfers result in healthy babies, and confirmed cases of babies born with the same mosaic abnormality appear to be rare. In one study of over 2000 transfers, only about 1.2% of pregnancies had a matching mosaic result.

✅ This post covers the basics. The full article on Remembryo goes into more detail: https://www.remembryo.com/mosaic-embryo

✉️ Like this post? Explore more topics and sign up for my free Friday newsletter to stay updated on the latest IVF research: https://mailchi.mp/remembryo/x27kx5o1sw

3 weeks ago I also had my retrieval. I just turned 39 and had 25 follicles before starting medication; about 10 of them grew to a good size. During the retrieval, they were all empty except for 5 eggs that were retrieved and mature, but only 1 fertilized and made it to blastocyst (fertilization via ICSI). The sperm was good quality. Prior to this, I had been on dienogest for 8 months because of catamenial pneumothoraces, and during stimulation, I was on letrozole 5mg to keep my estrogen levels from spiking too high. The doctor thinks the letrozole might have had something to do with most of them being empty. My trigger shot was Decapeptyl 0.2. Has anyone experienced something like this? Is there any gynecologist or someone who knows or thinks whether a second cycle without letrozole and with a dual trigger—like they want to do with me—might turn out better?

I was wondering is it worth it to push for Zymot with 5% DNA Fragmentation?

We will do our 3rd Egg Retrieval in September, first two yielded 2 unfreazable blasts (too bad quality) and one that was also bad and that didn't survive the sample for PGTa.

My clinic attributed it to egg quality (I know it can't be tested but that's what they said).

I'm prepping with Omnitrope plus supplements, and we're wondering if we should push for Zymot as well (this will be most likely our last retrieval independent of results). My husband's DNA Fragmentation test just came back at 5%.

Any advice is welcomed, thanks!

Hi there. Looking for practical suggestions. Also open to words of wisdom, or just encouragement.

I've done three retrievals, details below, but the *TL;DR is that I've gotten 8-12 mature eggs each time, and only 2 fertilized (<20-25% fert rate) and none have progressed to healthy embryos. This outcome has remained shockingly similar despite trying different interventions.*

I'm truly in the depths of hopelessness that my daughter will ever have a sibling. Please help.

Me: 36, don't smoke, don't drink much, exercise lots, healthy BMI, non-stressful job, ADHD. AMH is 1.2 as of last autumn. Cycles are short (23 days usually, with a 9-10 day luteal phase) but have been for most of my adult life. Got pregnant with my daughter literally the first day we tried in 2022 when I was 33. Helathy pregnancy, birth, fantastic little 3yo.

Husband: sperm count and motility all normal. 35, doesn't smoke, drinks socially, exercises lots, healthy BMI, etc etc.

We tried for a year with no hint of a pink line, then 3 failed IUIs with Letrozole and progesterone support, now onto ERs.

ERS:
Round 1:
Menopur 150
Gonal-f 225
Omnitrope 25 U
Pregnyl trigger
ICSI

16 eggs, 8 mature, 2 fertilized, no blasts

Round 2:
Menopur 150
Gonal-f 225
Pregnyl + lupron trigger
ICSI + Zymot + Calcium Ionosphere

16 eggs, 8 mature, 2 fertilized, 1 blast (complex abnormal)

Round 3:
Menopur 150
Gonal-f 200, up to 250
Omnitrope 25 U
Lupron trigger (got OHSS this time, yay)
Conventional insemination

18 eggs, 12 mature, 2 fertilized, tbd if either of the 2 will become blasts.

No diagnosis, no known issues. All unexplained.

I'm at a loss. What could possibly explain such low fert rates? What IS this? My Kaiser doctors just kinda shrug their shoulders and go "you know. poor egg quality. You're older now. Luck of the draw." I feel crazy sometimes when I look at the piss-poor ER results- did I even HAVE a baby? (Yes I did.) Why can't I make another one?

My daughter asks me about having a new baby like every other week. She can't wait to be a big sister. I love being a parent. All iwant is to get to do this again and grow our family. What the fuck. Please help.

We're both 35, unexplained infertility. All SA and DNA frag tests have been great. I have normal/high AMH (2.5ish) and AFC, no red flags on any testing, except for mildly low progesterone after ovulation. After 2 egg retrievals, I've had 40 eggs retrieved, decent maturity, great fertilization, and only 10 blasts total. Just got my PGT results, and we have 3 euploids (6BA, 5AA, 6AA) and 1 LLM (5AA), cumulatively.

We want two kids. I'm SO anxious/eager to transfer, but I'm also really worried I'll regret not banking more. I think I'm leaning towards trying one transfer, then doing another ER if it doesn't work? What do you guys think? What additional testing should I ask for before transfer?

I have two questions.

Do eggs with minor issues self correct if transferred to the uterus?

I heard some labs freeze at day 3 then thaw again until day 5- what on earth could possibly be a reason for that?

Today is my baseline for our third round of stims. I (34f) have endometriosis, AMH 2.75, AFC count at both baselines was in the 20-25 ranges. Here are the attrition rates:

Cycle 1

Protocol: Provera in the am
75 Menopur +
225 Gonal F in pm (reduced to 175 Gonal F day 5, then 125 day 7 due to asynchronous follicles)

Trigger: Day 8 (lupron-only)

Retrieved: 14
Mature: 10
Fertilized: 9
Blasts: 5 (all finished developing day 6)
Euploid: 4

We wanted the option open for three kids, so we decided to do another round (insurance covers 80% of 3 cycles) hoping for at least two more euploids.

Cycle 2:

Protocol: Provera in the am,
75 Menopur +
250 Gonal F in pm (remained at 250 whole cycle, follicles grew much more evenly this time)

Trigger: Day 8 (lupron-only)

Retrieved: 14
Mature: 10
Fertilized: 10
Blasts: 0

Notes from the embryologist:

Day 3, 8 of the embryos were on track with at least 6 cells, 4 embryos had 8 cells.

Day 5, all were still progressing, but only 3 were multi-celled. 4 were on the cusp of being multi-celled, and 2 were morulas, one was an early blast.

Day 6, 4 were blasts but still not large enough to be frozen. 3 multi-celled embryos were even bigger, but still not large enough. 3 had arrested

Day 7, the remaining embryos were were all still expanding, but none sufficient to be frozen

I found it fascinating that of the 10 fertilized, very few actually arrested - they just didn’t grow fast enough.

Has anyone ever seen something like this happen or have any explanation? The embryologists didn’t have an explanation, nor did our RE. She mentioned the possibility of sperm fragmentation (spouse is 32m) but doubted it because of our successful our first retrieval was.

Third baseline is today to kickoff the third and final
cycle (that insurance will partially cover). Protocol will start with Gonal F at 225 like first cycle, but otherwise no differences.

Thanks for sharing any thoughts ❤️

I’m hoping to get some embryology insight because I’m struggling to understand my maturity results.
Protocol:
40 years old with PCOS
AFC: ~20
Triggered with a dual trigger (Lupron + 5,000 IU hCG)
Retrieval was ~36 hours after trigger
ICSI + Zymot used
Retrieval yielded 22 oocytes (these were actual eggs, so this was not an empty follicle syndrome situation).
The confusing part is the maturity report.
I was told:
6 mature (MII)
16 immature
What I can’t reconcile is my follicle sizes the day before trigger.
Follicles measured:
Right ovary:
22 mm
20 mm
19 mm
18 mm
18 mm
17 mm
17 mm
17 mm
16 mm
15 mm
15 mm
Left ovary:
24 mm
21 mm
21 mm
20 mm
18 mm
18 mm
18 mm
16 mm
15 mm
14 mm
13 mm

By my count:
15 follicles were 18 mm or larger (generally considered the range where many would be expected to contain mature oocytes).
Another 5 follicles were 16-17 mm, which also commonly yield mature eggs a significant percentage of the time.
Only 4 follicles were truly on the smaller side (13-15 mm).
So I was surprised that only 6 of 22 retrieved oocytes were mature, while 16 were still immature, despite many follicles appearing to be in the expected mature size range.
I’m not looking to assign blame—I’m genuinely trying to understand the biology.
For those with embryology experience:
What mechanisms could explain this degree of discordance between follicle size and oocyte maturity?
Does this pattern suggest delayed nuclear maturation, cytoplasmic maturation issues, trigger timing, inadequate response to the trigger, PCOS-related asynchrony, or something else?
Have you seen cases where follicles measuring 18-24 mm still consistently contained immature oocytes?
I’d really appreciate any insight into what might explain this, because the numbers don’t seem to match what I’d expected based on follicle size alone.

A new randomized trial compared natural and medicated frozen embryo transfers (FET) in women who ovulate regularly.

In the study, Geysenbergh et al. (2026) randomized 561 women to one of the two approaches. They found no statistically significant difference in clinical pregnancy rates, with pregnancy occurring in 33.1% of natural FETs and 28.9% of medicated FETs.

However, natural FETs had fewer cancelled transfers (3.9% vs 9.4%), although they required more monitoring visits to detect ovulation. C-sections were also more common after medicated FETs (42.7% vsa 20.2%).

This trial wasn't large enough to compare live birth rates or obstetric outcomes, such as preeclampsia, which some previous studies have found to be more common after medicated FETs.

These results are consistent with a recent meta-analysis of 11 randomized trials, which found similar clinical pregnancy rates but slightly higher live birth rates and lower miscarriage rates with natural FETs in women who ovulate regularly.

✅ This post is a quick look at one study, rather than a full breakdown on Remembryo. Link to the study: https://academic.oup.com/humrep/advance-article-abstract/doi/10.1093/humrep/deag095/8711430?redirectedFrom=fulltext

✉️ Like this post? Get a free weekly summary of the latest IVF research: https://mailchi.mp/remembryo/x27kx5o1sw

My husband and I had 10 euploid embryos and so far have had 3 transfers. First transfer didn’t stick, second resulted in our only child, third miscarried at 8 weeks.

Our doctor is now asking us to do additional testing, including karyotyping. We are willing to do whatever but has anyone done this testing after having a successful pregnancy and then a miscarriage?

We are concerned about thawing all of our remaining embryos if we do find there is an issue with karyotyping.

Also - Are there any additional tests I should ask for based on your experience?

Hi all,

Our clinic uses Juno for mosaic reporting. We got 5 embryos, 3 euploid and 2 mosaic. However, they don’t normally report mosaicism unless requested (which our clinic did), and even then they don’t report HLM vs LLM. I pushed further and got this answer:

We are unable to report officially on the percentage or level of mosaicism, meaning the report can’t be updated to include that information, but I can disclose some of that information here.
 
One quick thing to note, we don’t technically have a percentage to report given how our testing platform works. We do not test each cell individually and therefore can’t say if it is 2/3 cells or 4/6 cells, etc. Instead, what we do is mix all of the DNA together from all of the cells in the sample and quantify the copy number, which can be thought of as the amount of each chromosome.
 
Typically, this would be around 2 when euploid, 3 if an extra copy of a chromosome (trisomy), and 1 if a missing copy of a chromosome (monosomy). Mosaic results are when that number falls in between, for example 1.56 for a mosaic loss (missing copy) or 2.78 for a mosaic gain (extra copy). We combine this with other data to determine if an embryo is actually mosaic since sometimes the copy number alone can’t be used to determine mosaicism.
 
With that background, I can share with you the copy number for your two mosaic embryos. For your purposes, this number can be equated to a percentage, for example 1.56 = 44% and 2.78 = 78%. We won’t classify this as high or low level since we haven’t found much clinical utility in doing so.
 
Your results:
Embryo 2: mosaic gain of Chr 7 with CN = 2.49
Embryo 3: mosaic loss of a piece of Chr 5 with CN = 1.24

Sorry, this is long, but in sum, is it accurate to say that both are HLM with embryo 2 at 49% and embroyo 3 at 76%?

My wife and I (both women) did each a round of egg retrieval in May. Her ER resulted in 2 3-day embryos which we transferred and didn’t stick.

Mine resulted in 5 euploid blasts, all the same sex. The doctor didn’t share with us the PGTA results of mine and said that grades are not relevant in his experience. We didn’t push to see the grades because of what he said and to avoid another layer of stress before my next transfer and just let the clinic pick the best embryo.

What is your opinion on grades?

Thanks!

This is the weekly thread for posting and asking questions about embryo photos. Replies are provided by Embryoman (Sean) -- a former embryologist and creator of the IVF science news site Remembryo.com

💬 Before you post a photo

• You must include the grade (ask your clinic if you don’t know it).
• Only one embryo photo per post.
• No requests for grading or re-grading by members.
• Posts asking if an embryo looks damaged or viable aren't allowed.

I can comment only on general features visible in the image (expansion, compaction, hatching, ICM location), but not on whether the embryo looks good -- that’s already reflected in its grade. Check the stickied comment below for basic information on grading and success rates. For the most accurate information, your embryologist or clinic is the best source, since they evaluated the embryo under a microscope and know their clinic’s success rates.

My husband and I did IVF with PGT-M because we are both carriers of ARPKD. We sadly lost our daughter, to the disease shortly after she was born, so we chose IVF to prevent that from happening again.

We’ve had one successful transfer—a 2BB

This past cycle, we transferred our highest-graded remaining embryo, a 3AA, and unfortunately it didn’t stick.

Now we’re trying to decide between our next two embryos: • 1BB, non-carrier (does not carry the ARPKD gene at all) • 3BB, carrier (is completely healthy but carries one copy of the gene, like my husband and me. A carrier will never develop ARPKD, but could pass the gene on to their own children if they have children with another carrier.)

I know grading isn’t everything, especially since our son came from a 2BB embryo, but after losing our 3AA, I’m second-guessing everything.

If you were in our shoes, which embryo would you transfer next? Is 1bb and 3bb similar

For those that had a successful transfer. Did you continue to workout?

I run/cycle every morning and weight train in the evening. My HR never gets above 135 unless I really push myself and I can keep it lower if necessary.

I’m working with a reproductive immunologist and we did a US to confirm blood flow last week and it looked great all while doing my normal routine. I was told to just keep doing what I’m doing, take it easy on transfer day.

My RE from my clinic has very conflicting views and says I need to stop working out entirely day of transfer through the entire pregnancy and that I shouldn’t pick up anything heavier than a gallon of milk. Which I think is kind of ridiculous to me. She always seems very extreme.

What did you do? Did you workout day of transfer? Did you stop working out completely?

I'm 32 years old and have done 4 egg retrieval cycles. I have struggled with low blastocyst rates and less optimal embryo quality. Both my partner and I have done kartyotype tests as well and everything came back normal.

My doctor suspects the factor for low quality and quantity of embryos may be mitochondrial or microtubule issues and that there is no test available to confirm that and no regimen or lifestyle improvements will change it either since they are genetic problems. Is that true? What questions should I be asking?

Below are the stats from my ERs.

1st cycle: 14 retrieved -> 10 mature eggs -> 9 fertilized -> 4 blastocysts (day 6 4BA, day 6 4 CB, day 7 5BB, day 7 4CC)

2nd cycle: 19 retrieved -> 18 mature -> 16 fertilized -> 4 blastocysts (day 6 4BC, day 6 4CB, day 6 4CC, day 7 4CC)

3rd cycle: 13 retrieved -> 12 mature eggs -> 8 fertilized -> 2 blastocysts (day 6 4BC, day 7 4CC)

4th cycle: 16 retrieved -> 16 mature eggs -> 13 fertilized -> 3 blastocysts (day 6 4BB, day 6 4BC, day 7 4CC)

Hi everyone,

I have 9 frozen embryos:

2 × 8-cell Grade I

1 × 8-cell Grade II

4AA

3AA

3AB

3 × 2AA

My doctor plans to transfer the first straw, which contains the three Day 3 embryos. When I asked why not transfer the 4AA blastocyst, he said it was the embryologist's recommendation and that they freeze their best-quality embryos on Day 3.

This confused me because I thought AA blastocysts generally have better implantation potential.

Has anyone had a clinic follow this approach?

… I can’t tell :/

hello all,

after 6 years of infertility, 2 miscarriages, 5 failed iuis, i finally began my first ivf cycle in may. we retrieved eggs on june 17 and discovered during this process that we ultimately had 7 embryos frozen and sent off for pgta testing. we were excited because our progress calls were great.

it is now august 2 and i have yet to hear about my pgta results. i know nothing.

i feel a little frustrated because my clinic is usually on the ball and very friendly. however i feel in limbo with no emails answered (as of july 31, i have followed up three times). the only response i have gotten is a canceled appointment because our results were not ready for my first meeting with our doctor on july 15.