Here you’ll find a brief summary of new IVF studies for February* that I think are helpful for patients. I’ll be updating this post each week of February with new studies, before making a separate post for next month.
*Note that the publication dates of these studies might be outside of the indicated period, mostly because of how PubMed indexes the article.
🔗 Original studies are referenced in this post or within the linked Remembryo posts.
💡 Reminder: Terms underlined with a dotted black line are linked to glossary entries. Clicking these does not count toward your paywall limit.
Table of Contents
Week 1 (Jan 30 – Feb 5)
Molecular profiling of human blastocysts reveals primitive endoderm defects among embryos of decreased implantation potential. This study compares gene expression in mouse embryos that are good or poor quality to identify factors involved in implantation. They found that poor quality embryos had delayed development of the primitive endoderm, a group of inner cell mass cells that give rise to the yolk sac.
Potential Costs and Benefits of Incorporating PGT-A Across Age Groups: A Canadian Clinic Perspective. This study assessed the costs and benefits of PGT-A across age groups, finding that PGT-A was most advantageous for women aged 38 and above. They found that embryo grades alone were able to predict euploid embryos 78% of the time in women <35, but only 32% of the time in women 38 and older.
What is the impact of endometriosis and the AFS stage on cumulative pregnancy rates in IVF programs? This study compared IVF ongoing and cumulative pregnancy rates for women with endometriosis. Overall, they found no difference for women with or without endometriosis, but found reduced cumulative pregnancy rates for women with stage 3/4 endometriosis.
The Association between Embryo Development and Chromosomal Results from PGT-A in Women of Advanced Age: A Prospective Cohort Study. Day 3 and day 5 embryos were evaluated for their potential to become euploid embryos, based on cell number or grade. Embryos that were more advanced and with good quality grades were more likely to become euploid. To read more about factors that influence whether you get a euploid or not, check here.
Clinical and neonatal outcomes of complete zona pellucida removal by laser-assisted hatching after single vitrified-warmed blastocyst transfer. In this study, blastocysts had their zona artificially removed, which resulted in higher live birth rates compared to blastocysts with intact zonas. This study found no difference when zonas were removed.
Week 2 (Feb 6 – Feb 12)
Live Birth After Oocyte Donation In Vitro Fertilization Cycles in Women With Endometriosis: A Systematic Review and Meta-Analysis. This meta-analysis combined data from 4 studies and 2 IVF registries, and found similar live birth rates in donor egg cycles in patients with or without endometriosis. When the researchers compared only the IVF registry data, they found a decrease in live birth rates in patients with endometriosis. This meta-analysis also found no difference in live birth rates in patients with or without endometriosis.
Development and validation of a clinical prediction model of fertilization failure during routine IVF cycles. This study built a model to predict fertilization failure with an AUC of 0.776. This was based on infertility years, basal oestrogen, the rate of mature oocytes, oligoasthenozoospermia, sperm concentration, sperm vitality, percentage of abnormal morphological sperm, and percentage of progressive motility.
The optimal timing of frozen-thawed embryo transfer: delayed or not delayed? A systematic review and meta-analysis. This meta-analysis combined the results of 19 studies that looked at FETs that were either delayed by at least a month or not. There was no difference in live birth or clinical pregnancy rates.
Correlation of self-reported racial background to euploidy status and live birth rates in assisted reproductive technology cycles. This study wanted to see if there was any difference in euploidy rates or live births after a single euploid transfer in women with different racial/ethnic backgrounds. They found that euploidy rates and pregnancy outcomes were comparable.
No matter how you slice it, increasing body mass index is associated with a lower probability of live birth…or is it? This is a commentary that looks at 3 recent studies comparing BMI and pregnancy outcomes in patients transferring euploids or using donor eggs. The 3 studies found that “increasing BMI is probably associated with a lower probability of [live birth]. However, there is still a lot that we do not know,” including whether the endometrium, the egg, or both are affected with increased BMI. This study also found that increased BMI resulted in decreased live birth rates after a euploid transfer.
Week 3 (Feb 13 – Feb 19)
Comparative efficacy of different growth hormone supplementation protocols in improving clinical outcomes in women with poor ovarian response undergoing assisted reproductive therapy: a network meta-analysis. This meta-analysis combined the results of 23 studies looking at growth hormone (omnitrope) supplementation. They found that certain protocols were effective in improving clinical pregnancy rates in patients with poor ovarian response. This meta-analysis also found a benefit in using growth hormone.
The effect of laser assisted hatching on vitrified/warmed blastocysts:the ALADDIN randomized controlled trial. This randomized controlled trial (RCT) evaluated the use of partial zona removal through assisted hatching, where about one-third of the zona was removed before transfer. There was no difference in live birth rate. This meta-analysis found a benefit for assisted hatching.
Intracytoplasmic sperm injection versus conventional in-vitro fertilisation for couples with infertility with non-severe male factor: a multicentre, open-label, randomised controlled trial. This randomized controlled trial (RCT) evaluated the use of ICSI for non-severe male factor patients compared to conventional IVF. There was no difference in live birth rates. This meta-analysis found no benefit for ICSI over conventional IVF for non-male factor.
Intravaginal exposure to seminal plasma after ovum pick up does not increase live birth rates after IVF or ICSI: a double-blind, placebo-controlled randomized trial. This randomized controlled (RCT) evaluated pregnancy outcomes after applying intravaginal seminal plasma on the day of the egg retrieval. There was no difference in clinical pregnancies or live births. This study found that protected sex before embryo transfer led to improved pregnancy rates.
Association between proliferative-to-secretory endometrial compaction and pregnancy outcomes after embryo transfer: a systematic review and meta-analysis. This meta-analysis combined the results of 17 studies to see if there was any effect of endometrial compaction on pregnancy outcomes. For patients with or without endometrial compaction, they found no differences in clinical pregnancies, live births and more.
Week 4 (Feb 20 – Feb 26)
Comparative analysis of pregnancy outcomes in PGT-A and conventional IVF-ET: a stratified examination based on quantity of oocyte and blastocyst from a multicenter randomized controlled trial. Over 1,200 good prognosis patients underwent PGT-A or didn’t and were split up into groups based on how many eggs were retrieved. They found a lower cumulative pregnancy loss rate with PGT-A in the <15 egg group, and a lower cumulative live birth rate with PGT-A in the 19-23 egg group, but no differences in the other groups.
The impact of microfluidics sperm processing on blastocyst euploidy rates compared to density gradient centrifugation: a sibling oocyte double-blinded prospective randomized clinical trial. This study compared PGT-A results from blastocysts that were made using Zymot or traditional sperm processing methods. They found no differences in the euploidy rate and the number of high quality blastocysts produced, but there was higher fertilization with Zymot (76.0% vs 69.9%). This study was funded by Zymot.
The use of immunomodulation therapy in women with recurrent implantation failure undergoing assisted conception: A multicentre cohort study. This study compared live birth rates after using immunotherapies (corticosteroids, low molecular weight heparin and/or intralipids) in over 5,000 women with recurrent implantation failure who were diagnosed with immune issues. They found improved live births in women who had immunotherapies. This is in contrast to a recent meta-analysis, although most studies don’t test these treatments in patients with existing immune issues.
Blastocysts from partial compaction morulae are not defined by their early mistakes. This study compared euploidy rates and pregnancy outcomes in morulas (day 4 embryos) that either had fully compacted or partially compacted. They found that partially compacted morulae were less likely to form blastocyts, but had equivalent euploidy rates and live birth rates to fully compacted morulae.
Assessment of Clinical Pregnancies in Up to Eight Ovarian Stimulation with Intrauterine Insemination Cycles in Those Unable to Proceed With In Vitro Fertilization. This study compared nearly 40,000 IVF cycles to examine the chance of pregnancy after up to 8 cycles. In their statistical model, they found that the cumulative predicted pregnancy rate increased after each cycle.
Week 5 (Feb 27 – Mar 4)
Predictive Factors for the Formation of Viable Embryos in Subfertile Patients with Diminished Ovarian Reserve: A Clinical Prediction Study. Researchers developed a type of calculator called a nomogram to help predict blastocyst formation in patients with DOR. This was based on maternal age, fertilization and day 3 embryo grade.
Effectiveness of preconception weight loss interventions on fertility in women: a systematic review and meta-analysis. This meta-analysis combined the results of 40 studies that investigated if weight loss interventions improved pregnancy, live birth and miscarriage rates. They found improvements in pregnancy rates, but no differences in live birth or miscarriage rates, with women with a BMI 35 or higher showing the most benefit.
Preimplantation genetic testing for aneuploidy: predictive embryonic factors. Embryo quality, day of blastocyst formation and hatching status were compared to euploidy and thaw-survival rates after PGT-A. Higher quality embryos, and blastocysts that formed on day 5, were more likely to be euploid and had a higher chance of survival after thawing. Fully hatched blastocysts had a lower survival rate.
Effect of Hyaluronic Acid-Containing Transfer Media (EmbryoGlue®) on the Live Birth Rate in Frozen Thawed Embryo Transfer Cycles. This multicenter study focused on pregnancy outcomes after using EmbryoGlue (hyaluronic acid) in embryo transfer culture media. Embryo Glue improved live birth and clinical pregnancy outcomes. A recent meta-analysis found a benefit in using embryo glue.
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