u/embryomanofficial

The Uterine Wall of Fame (UWOF) is a collection of real IVF success stories from people with difficult fertility journeys -- low-grade embryos, repeated failures, low AMH, mosaic results, and more. 

UWOF #44 is one of those stories. At 35, she had eight embryos from one retrieval, but six transfers were unsuccessful. Their seventh transfer, a day 5 3BB embryo, led to an ongoing pregnancy.

✅ Visit the UWOF to read this story and others like it (free to access & no subscription required): https://remembryo.com/uwof44-after-six-failed-transfers-our-seventh-embryo-stuck/

💌 Have a story of your own? Can be anonymous or named: https://www.remembryo.com/uterine-wall-of-fame-submission-form/

⚠️ These are personal stories, not medical advice or scientific evidence. A success story isn't proof of what made the difference. Always discuss treatment decisions with your fertility specialist.

September’s IVF Research Roundup is live!

🔹 New study highlights

🔹 IVF research & news

🔹 ~40 research study summaries (subscribers only)

📌 Post is free to read (no paywall): https://remembryo.com/monthly-ivf-research-roundup-september-2026/

(Sponsored by Reticular)

Small genetic changes may help explain some recurrent euploid pregnancy losses.

An embryo can have the expected number of chromosomes (euploid) and still carry small changes within individual genes. Most are harmless, but some may affect development and increase miscarriage risk. PGT-A isn’t designed to detect most of these smaller changes.

Researchers in a 2025 study tested pregnancy loss tissue and parental DNA from 118 families with unexplained recurrent euploid pregnancy loss. Euploidy was confirmed by testing tissue after the loss, rather than through PGT-A before embryo transfer.

They found a possible genetic explanation in about 25% of families. Most findings were inherited from one or both parents.

Some genetic variants (mutations) had stronger evidence of being harmful than others. Animal research helped assess some findings, but identifying a variant didn’t prove that it caused that particular pregnancy loss.

I think this is a promising research direction that could help explain otherwise unexplained losses and provide more informed genetic counselling. However, the study is a preprint and hasn’t yet been peer reviewed. It also didn’t specifically examine losses after IVF or euploid embryo transfer. More research is needed to see whether using this information to guide embryo selection improves reproductive outcomes.

✅ Read the full article for free on Remembryo—no paywall: https://remembryo.com/small-genetic-mutations-may-explain-some-euploid-pregnancy-losses/

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

Women who become gestational surrogates often have had a previous healthy pregnancy of their own. Researchers wanted to know if pregnancies with a gestational surrogate have different risks than the surrogate's own previous pregnancies.

In a new systematic review, Barry et al. (2026) reviewed the available evidence comparing these pregnancies.

Compared with the surrogate's own previous pregnancies, gestational surrogacy was associated with higher rates of pre-eclampsia or gestational hypertension, gestational diabetes, and preterm birth.

The authors suggest this may be because pregnancies involving a genetically unrelated embryo could produce a different immune response during implantation and placental development. However, hormone treatments used during a medicated frozen embryo transfer may also contribute, and the exact reason isn't clear.

Importantly, the available evidence was limited and many of the studies were small or at high risk of bias. More research is needed before firm conclusions can be drawn.

✅ This post is a quick look at one study, rather than a full breakdown on Remembryo. Link to the study: https://link.springer.com/article/10.1007/s10815-026-04003-z

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

A clinical pregnancy, even if it ended in miscarriage, might be a positive sign for a future IVF cycle.

After an unsuccessful cycle, patients wonder if this offers any clues about what might happen next.

Pape et al. (2026) studied 1860 women in the Swiss national IVF registry who completed two consecutive complete IVF cycles. Each cycle included one egg retrieval and all transfers from it.

Patients who had a clinical pregnancy or live birth during their first cycle had higher odds of live birth during their second cycle (compared to those who didn’t get pregnant).

A biochemical pregnancy wasn’t linked with better results. The authors noted that it may still be a positive sign compared with no pregnancy, but it shouldn’t be used alone to predict future IVF success.

Importantly, not getting pregnant during the first cycle didn’t mean the second cycle would also fail; many of these patients still had a live birth.

Age and the number of eggs retrieved were also important.

The study didn’t include PGT-A cycles and only included patients who returned for and completed a second cycle, so the results won’t apply equally to everyone.

✅ Check out the full article and more details on Remembryo: https://remembryo.com/first-ivf-cycle-results-may-offer-clues-about-the-next/

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

What is embryo compaction?

A compacted embryo is a blastocyst that has temporarily collapsed into a tighter ball of cells. It could also be called a "collapsed" or "contracted" blastocyst.

When an embryo looks compacted, it's sometimes harder to clearly see the inner cell mass and trophectoderm, which are the structures used for grading.

Blastocysts contain a fluid filled cavity called the blastocoel. This cavity is normally filled with water.

When water leaves the blastocoel, the embryo deflates and appears compacted, just like a balloon shrinking when fluid or air is released. The trophectoderm forms the outer layer, and the blastocoel sits inside as the fluid filled space.

Compaction is part of normal embryo development. Embryos naturally go through cycles of expansion and contraction as they take up and release fluid.

But embryos can also be collapsed in the lab. This is usually done before freezing to remove water and reduce the risk of damage from ice crystals that could form. After thawing, an embryo could still look compacted when a photo is taken, because it might not have had enough time to re-expand.

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

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

The Uterine Wall of Fame (UWOF) is a collection of real IVF success stories from people with difficult fertility journeys -- low-grade embryos, repeated failures, low AMH, mosaic results, and more. 

UWOF #42 is one of those stories. After 6 unsuccessful embryo transfers, only 2 eggs fertilized during her third retrieval. Both reached Day 5, and a fresh transfer led to her baby boy.

✅ Visit the UWOF to read this story and others like it (free to access & no subscription required): https://remembryo.com/uwof42-after-6-failed-transfers-only-2-eggs-fertilized/

💌 Have a story of your own? Can be anonymous or named: https://www.remembryo.com/uterine-wall-of-fame-submission-form/

⚠️ These are personal stories, not medical advice or scientific evidence. A success story isn't proof of what made the difference. Always discuss treatment decisions with your fertility specialist.

The Uterine Wall of Fame (UWOF) is a collection of real IVF success stories from people with difficult fertility journeys -- low-grade embryos, repeated failures, low AMH, mosaic results, and more. 

UWOF #41 is one of those stories. After 8 years, 3 egg retrievals, undiagnosed endometriosis, and 4 unsuccessful embryo transfers, Kelly’s fifth transfer (a day 5 4AA euploid embryo) led to a healthy baby boy.

✅ Visit the UWOF to read this story and others like it (free to access & no subscription required): https://remembryo.com/uwof41-undiagnosed-endometriosis-and-4-failed-transfers/

💌 Have a story of your own? Can be anonymous or named: https://www.remembryo.com/uterine-wall-of-fame-submission-form/

⚠️ These are personal stories, not medical advice or scientific evidence. A success story isn't proof of what made the difference. Always discuss treatment decisions with your fertility specialist.

Embryos created during IVF are grown in a special liquid called an embryo culture medium, which provides nutrients and supports their development before transfer or freezing. There are many commercially available media, including G5, HTF, Global, and Sydney IVF, but it's still unclear whether one performs better than another.

In this updated Cochrane review, Laverde et al. (2026) analyzed 26 randomized trials comparing different embryo culture media.

One study suggested that G5 may improve cumulative live birth compared with HTF, but overall the studies compared different culture media, making it impossible to combine the results in a meta-analysis. Most comparisons also showed no clear differences in live birth or ongoing pregnancy rates.

The authors also noted that many studies were small or used study designs that made it difficult to determine which culture medium performs best. Larger, well-designed randomized trials are still needed.

"There is currently no clear agreement on which type of embryo culture medium gives the best chances of having a live baby. The available research does not give enough reliable information to clearly choose one culture medium over another."

✅ This post is a quick look at one study, rather than a full breakdown on Remembryo: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD007876.pub3/full

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

How many euploid embryos do you need to have a baby?

Large studies of patients transferring euploid embryos one at a time suggest that the overall chance of having at least one live birth is about:

1 euploid: 63–65%
2 euploids: 83–84%
3 euploids: 92–93%
4 euploids: 96%
5 euploids: 98%

This helps explain the common rule of thumb that it takes about three euploid embryos per baby. But that's not exactly what the evidence shows.

Many patients won't need three. About 63–65% had a live birth after their first transfer, and these numbers are population averages, not predictions for an individual patient.

These studies estimated the chance of at least one live birth across groups of patients, but they can't predict how many embryos an individual patient will actually need. Some patients will have a live birth after their first transfer, while others may need several.

And if the first euploid transfer fails, the next embryo can still have a good chance of success. In the largest study, live birth rates remained around 50–58% per transfer from the second through fifth attempts.

Euploid embryos aren't all equivalent either. Developmental day, embryo grade, age, and other patient and clinic factors may affect the chance of success.

I've put together a new Evidence Guide that includes the evidence behind these estimates, what happens after failed transfers, factors that may change success, important evidence gaps, and interactive calculators for subscribers.

✅ Check out more details on Remembryo: https://remembryo.com/how-many-euploid-embryos-do-i-need-to-have-a-baby/

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

Many people going through IVF have issues with poor sleep, anxiety, or depression, but it's not clear if this has any affect on the chance of success.

In a new study, Wang et al. (2026) evaluated 15,642 women before their first IVF or ICSI cycle using questionnaires on sleep quality, anxiety, depression, and physical symptoms.

Among the 11,986 women who went on to have an embryo transfer, women with better subjective sleep quality had a 2.6% higher relative chance of achieving a clinical pregnancy after adjusting for other factors. Note that this is a relative increase, not an absolute one. For example, if the chance of pregnancy was 50%, a 2.6% relative increase would raise it to about 51.3%, not 52.6%.

Anxiety, depression, and physical symptoms were not significantly associated with success rates.

The researchers also found that women who reported using sleep medication had a lower risk of late miscarriage. However, this was based on just three late miscarriages in sleep medication users, so it could have simply been due to chance.

This was an observational study, so it can't show that improving sleep will improve IVF outcomes. However, it adds to evidence that sleep may be one factor worth studying further during fertility treatment.

✅ This post is a quick look at one study, rather than a full breakdown on Remembryo. Link to the study: https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2026.1884236/full

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

Even when they were euploid, day 7 blastocysts had lower live birth rates than day 5 or day 6 blastocysts, but they still had meaningful potential for success.

Day 7 blastocysts develop more slowly, and not all IVF labs routinely culture embryos to day 7. Extending culture to day 7 may allow some additional embryos to reach the blastocyst stage.

Firmin et al. (2026) combined 17 studies to examine how these embryos perform compared with day 5 and day 6 blastocysts.

For untested blastocysts, live birth rates were 17% for day 7, compared with 44% for day 5 and 34% for day 6. Clinical pregnancy rates were also lower.

There was still a difference after PGT-A. Among euploid blastocysts, live birth rates were about 23% for day 7, 59% for day 5, and 45% for day 6. Day 7 blastocysts were also less likely to be euploid.

Miscarriage was also higher for day 7 than day 5 blastocysts. However, there was no significant difference in miscarriage between day 7 and day 6 blastocysts.

This research shows that day 7 blastocysts have potential, and the authors highlight their value for patients with few or no other embryos available, writing that they deserve consideration “rather than being dismissed outright.”

✅ Check out more details on Remembryo: https://remembryo.com/do-day-7-blastocysts-perform-as-well-as-day-5-or-day-6/

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

The Uterine Wall of Fame (UWOF) is a collection of real IVF success stories from people with difficult fertility journeys -- low-grade embryos, repeated failures, low AMH, mosaic results, and more. 

UWOF #40 is one of those stories. Michelle conceived after 7.5 years, 8 egg retrievals, and 11 embryo transfers when a Day 5 4BC complex low-level mosaic embryo finally implanted. She was 17 weeks pregnant with a baby boy when she shared her story.

✅ Visit the UWOF to read this story and others like it (free to access & no subscription required): https://remembryo.com/uwof40-11-transfers-later-a-complex-mosaic-embryo-worked/

💌 Have a story of your own? Can be anonymous or named: https://www.remembryo.com/uterine-wall-of-fame-submission-form/

⚠️ These are personal stories, not medical advice or scientific evidence. A success story isn't proof of what made the difference. Always discuss treatment decisions with your fertility specialist.

Correction: They started IVF in 2021, but had been trying for 7.5 years in total.

Childhood experiences can affect long-term health, but researchers are still learning whether they can also influence fertility.

In a new study, Bromark et al. (2026) analyzed data from more than 22,000 women in Norway. Women reporting a difficult childhood had 35% higher odds of infertility (about 20% vs 16%), along with higher odds of preterm birth and having a baby born small for gestational age.

Childhood adversity included experiences such as parental divorce or death, growing up in a dysfunctional family, lack of support from a trusted adult, abuse, bullying, or struggling with bad childhood memories.

The authors shared several possible explanations for these results. Childhood adversity may lead to long-term stress that affects reproductive hormone regulation, or it may influence factors like smoking, body weight, education, and socioeconomic status, which can also affect fertility.

✅ This post is a quick look at one study, rather than a full breakdown on Remembryo. Link to the study: https://www.fertstert.org/article/S0015-0282(26)00576-5/fulltext

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

Most children conceived through IVF appear to have similar long-term health to those conceived without fertility treatment.

Many people worry about whether IVF could affect their child's health later in life. To help answer that question, two large reviews by Le et al. (2026) and Firmin et al. (2026) summarized nearly 150 studies examining the long-term health of children conceived through IVF and ICSI.

Overall, the evidence found:

• Most birth defects and cardiovascular and metabolic outcomes were similar after IVF, although a few differences were reported.

• Brain development, growth, asthma, diabetes, and cancer were generally similar.

• Children conceived through ICSI had similar long-term health to those conceived through conventional IVF, with only some reported differences.

• PGT wasn't associated with differences in children's growth, blood pressure, or metabolic health, but longer-term data are still needed.

• Fresh and frozen embryo transfers differed in birth weight.

One important challenge is separating the effects of IVF itself from the effects of the parents' underlying infertility. Some of the reported differences may be related to infertility itself rather than the fertility treatment, but it's still not clear how much each contributes.

Overall, the evidence is reassuring. Importantly, most of the conditions studied were rare, affecting fewer than 1% of children. This means that even when an increased risk was found, the actual increase in the chance of developing the condition was very small.

✅ Check out more details on Remembryo: https://remembryo.com/do-children-conceived-through-ivf-have-long-term-health-problems/

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

The embryo is the biggest factor in whether implantation succeeds, but even after transferring a euploid embryo, many other factors can influence the chances of pregnancy.

Some of these include:

• Endometrial receptivity: The uterine lining must be ready to receive the embryo during a short window of implantation.

• The immune system: Implantation requires a carefully balanced immune response. In some patients, abnormal immune function may interfere with implantation.

• Endometriosis and adenomyosis: These conditions can alter the uterine environment through inflammation, hormone signaling, and changes in uterine function.

• Structural abnormalities: Fibroids, polyps, adhesions, hydrosalpinx, and uterine anomalies can reduce implantation by disrupting the uterine cavity or affecting endometrial function.

• Endometritis: Infection or chronic inflammation of the endometrium can reduce implantation and increase the risk of miscarriage.

• The microbiome: Changes in the bacteria living in the reproductive tract may also affect implantation, although the evidence is still evolving.

• Lifestyle and metabolic health: Smoking, obesity, insulin resistance, and other health factors may reduce the chances of a successful pregnancy.

• Clinical and lab factors: Embryo transfer technique and IVF laboratory performance can also influence outcomes.

Still, the exact reason a transfer failed often remains unknown. Implantation is one of the most complex processes in human reproduction, and researchers are still working to understand why some embryos implant while others don't.

✅ This post covers the basics. The full article on Remembryo goes into more detail: https://remembryo.com/why-do-embryos-in-ivf-fail-to-implant-or-miscarry/

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

After egg retrieval, some eggs are still immature and are often discarded.

Rescue in vitro maturation (IVM) is a technique where embryologists culture these immature eggs in the lab, often overnight, to give them time to mature before insemination.

In a new study, Cimadomo et al. (2026) performed rescue IVM on the most immature type of egg, called germinal vesicle (GV) oocytes.

Overall, 53.7% of GV eggs matured, but they were less likely to reach the blastocyst stage than eggs that were already mature when collected. However, blastocysts that did develop were just as likely to be euploid, and rescue IVM provided at least one additional euploid embryo in 11 of 47 patients. Overall, this contributed to a 20% relative increase in cumulative live birth rate.

This was a small retrospective study of patients with unexpectedly poor egg maturation. While larger studies are still needed, the results suggest that rescue IVM may provide another opportunity to obtain a transferable embryo instead of discarding these immature eggs.

✅ 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/doi/10.1093/humrep/deag115/8733590?login=false

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

Researchers have looked at whether having sex before or after embryo transfer affects implantation or pregnancy rates, but the evidence is still mixed.

Many fertility clinics recommend avoiding sex around embryo transfer, with common reasons including concerns about uterine contractions after orgasm, a small risk of infection after embryo transfer, and (during natural frozen cycles) a small chance of a simultaneous spontaneous pregnancy.

A few studies have investigated if sex around embryo transfer affects success rates.

A new 2026 study of more than 1,300 women found no difference in pregnancy, live birth, or pregnancy loss rates between women who had sex during endometrial preparation and those who didn't.

Most earlier studies found similar results. However, one randomized trial found higher implantation and clinical pregnancy rates when couples had protected sex the night before frozen embryo transfer.

Researchers have suggested that sex might help implantation due to increased blood flow, hormonal changes, or improved immune signaling. One leading theory is that seminal plasma may help prepare the mother's immune system for pregnancy.

Interestingly, the only randomized trial to find a benefit involved protected sex, suggesting the explanation may be more complex than exposure to seminal plasma alone.

Overall, there isn't enough high-quality evidence to conclude that having sex around embryo transfer either improves or harms IVF outcomes.

✅ Check out more details on Remembryo: https://remembryo.com/does-sex-before-or-after-embryo-transfer-affect-implantation-or-pregnancy/

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

Researchers found that more than two-thirds of patients with complete embryo arrest still developed at least one usable blastocyst in their next IVF cycle.

Embryo arrest generally occurs when an embryo stops developing before reaching the blastocyst stage. However, IVF labs don't all use the same criteria for what they consider a usable blastocyst.

George et al. (2026) studied nearly 4000 patients who had two IVF cycles within one year to see if complete embryo arrest in the first cycle affected usable blastocyst formation in the next cycle. The study included PGT-A cycles, where only blastocysts that met the laboratory's biopsy and freezing criteria were counted (at least grade 4CC by day 7).

Patients with complete embryo arrest had lower usable blastocyst formation rates in their next cycle, and were more likely to experience complete embryo arrest again.

However, more than two-thirds of these patients still developed at least one usable blastocyst in their next cycle. Among the usable blastocysts that formed, the chances of being euploid and leading to a live birth after transferring a single euploid embryo were similar.

The researchers also found no evidence that changing the ovarian stimulation protocol or trigger medication improved usable blastocyst formation.

A limitation of this study is that they only counted usable blastocysts (at least grade 4CC by day 7), so the reported blastocyst formation rates excluded some blastocysts that didn't meet the lab's biopsy and freezing criteria.

✅ Check out more details on Remembryo: https://remembryo.com/what-to-expect-after-complete-embryo-arrest-during-ivf/

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