Monthly IVF research brief for November 2024

Here you’ll find a brief summary of new IVF studies for November* that I think are helpful for patients. I’ll be updating this post each week of November 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.

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Week 1 (Oct 29 – Nov 4)

Preconception alcohol consumption in both partners and risk of miscarriage. The PRESTO study tracked couples trying to conceive and found that drinking alcohol before conception, by either partner, did not increase the risk of miscarriage. This result held true for different types of alcohol and across various demographic groups.

Risk factors for mismatch in the ART laboratory: an analysis of 73719 electronic witnessing points. The study examined risk factors for mismatches in an IVF lab using an electronic witnessing system, analyzing over 73,000 witnessing points from 11,210 treatment cycles. Mismatches were most common during the embryo transfer process and specific times of day, with critical mismatches occurring most frequently after 4pm during oocyte denudation.

Safety concerns of paternal drug exposure on fertility, pregnancy and offspring: An analysis based on the FDA adverse event reporting system. The study utilized the FDA adverse event reporting system (FAERS) to analyze the impact of paternal drug exposure on fertility, pregnancy outcomes, and offspring health. It revealed significant safety signals, particularly diazepam’s link to smaller babies, indicating a strong influence of paternal medications on reproductive health, with drugs for rheumatoid arthritis, cancer, and infections being the most commonly reported.

Reassessing the conventional fertilisation check: leveraging PGT-A to increase the number of transferrable embryos. The study explored the viability of non-2PN zygotes for embryo transfer after assessing their diploidy through PGT-A (diploid means they have the right number of sets of chromosomes, ie. 2 copies). It found that over 60% of non-2PN embryos were diploid, and that 98.2% of 2PNs were diploid.

Consumer wearables and personal devices for tracking the fertile window. The review looks at the growing US market for ovulation tracking devices, identifying 23 types that use temperature or hormone levels to help women find their fertile window. It points out the lack of detailed research on these devices’ accuracy, discusses their usefulness and cost, and calls for more affordable, innovative solutions to improve access.

Week 2 (Nov 5 – Nov 11)

Chromosomal abnormalities in oocyte donor candidates: a French survey of over 8200 karyotypes. This study examined over 8,200 oocyte donor candidates and found that 65 carried chromosomal abnormalities (0.79%), with reciprocal translocations 5 times higher in donors without children. This research suggests that karyotyping could help detect genetic risks in donors that could be missed using questionnaires.

Impact of BMI on fertility in an otherwise healthy population: a systematic review and meta-analysis. This meta-analysis combined the results of 9 studies and found that higher BMI negatively impacts assisted reproductive technology (ART) outcomes in women without other medical conditions, leading to lower pregnancy rates, longer stimulation times and fewer eggs retrieved.

Intrauterine infusion of autologous platelet rich plasma can be an efficient treatment for patients with unexplained recurrent implantation failure. This randomized controlled trial (high quality study) found that intrauterine PRP in patients with recurrent implantation failure (RIF) improved clinical pregnancy and live birth rates, but also increased pregnancy complications.

Cytoplasmic strings in human blastocysts: hypotheses of their role and implications for embryo selection. This study found that cytoplasmic strings, commonly seen in human embryo pictures, are linked to faster blastocyst development, larger expansion, and better quality.

High-intensity focused ultrasound in adenomyosis treatment: Insights on safety, efficacy, and reproductive prospects. This review examines the role of high-intensity focused ultrasound as a non-invasive treatment for adenomyosis.

Week 3 (Nov 12 – Nov 18)

Triggering oocyte maturation in IVF treatment in normal responders: a systematic review and network meta-analysis. This meta-analysis combined the results of 12 randomized controlled studies (high quality studies) that compared different triggers (hCG, GnRH agonist, dual, and double triggers) in women undergoing ovarian stimulation for IVF. While the dual trigger showed potential benefits, the results are constrained by the limited number of RCTs, particularly concerning long-term outcomes and OHSS rates.

Human oocyte zona pellucida abnormalities: evaluation of clinical impact for different zona pellucida abnormalities and role of using assisted hatching. This study analyzed the effects of abnormalities in the zona pellucida, the shell surrounding the egg, and showed that patients with abnormal zonas had lower IVF success rates. Assisted hatching on day 1 improved embryo development for these patients.

Exogenous progesterone rescue in patients with low mid-luteal serum progesterone levels undergoing true natural vitrified-warmed blastocyst transfer. This study evaluated the impact of administering 25 mg of progesterone daily to patients with low serum progesterone levels (7–10 ng/mL) before a true natural cycle frozen embryo transfer. The results showed that additional progesterone did not significantly improve live birth rates compared to patients that didn’t receive additional progesterone.

Innovations in reproductive medicine, Gartner hype cycle and Dunning–Kruger effect. This paper investigates how the Dunning-Kruger effect, which describes how people with low knowledge overestimate their abilities, influences the “hype” of new innovations in reproductive medicine. Using the endometrial scratch as an example, it advocates for stricter evaluation and evidence-based practices before new interventions are widely adopted, to prevent harm and ensure they are truly beneficial.

THE EFFECTS OF THE BRCA1 AND 2 MUTATIONS ON OVARIAN RESERVE AND AGING. The study examined the impact of BRCA1 and BRCA2 mutations on ovarian reserve by assessing follicle density and DNA damage in oocytes. It found that BRCA1 carriers had significantly reduced primordial follicle density, indicating a diminished ovarian reserve, and both BRCA1 and BRCA2 carriers exhibited higher levels of DNA damage.

Week 4 (Nov 19 – Nov 25)

Assessing the impact of calcium ionophore on pregnancy outcomes in artificial oocyte activation cycles: a 10-year update of systematic review and meta-analysis. A meta-analysis combined the results of 12 studies investigating the use of artificial oocyte activation by calcium ionophore in improving pregnancy outcomes after IVF. They found an improvement in fertilization rates and live birth rates, with no change in miscarriage rates, especially in patients with fertilization issues. There were no improvements in patients without fertilization problems.

A systematic review and meta-analysis of double trophectoderm biopsy and/or cryopreservation in PGT: balancing the need for a diagnosis against the risk of harm. A meta-analysis combined the results of 10 studies investigating the impact of double embryo biopsy and/or double freezing/thawing (ie. cases where a patient wants to thaw an unbiopsied embryo for biopsy). Patients that had a repeat biopsy and/or double freezing/warming had lower live birth rates and higher miscarriage rates.

Women may not benefit from repeated frozen embryo transfers: a retrospective analysis of the cumulative live birth rate of 43 972 women. This study compared cumulative live birth rates for over 43,000 women aged <30 to >44, while also considering the number of retrieved eggs and type of infertility.

Does cleavage- versus blastocyst-stage embryo transfer improve fertility rates in women over 38 years of age undergoing assisted reproductive technology? This study compared day 3 vs day 5 embryo transfer in older patients. They found a higher cancellation rate for day 5 patients, and no difference in clinical pregnancy and live birth rates.

Assessing the clinical value of day 7 blastocysts: a predictive model for preimplantation genetic testing for aneuploidy (PGT-A) cycles. This study investigated the potential of day 7 embryos compared to day 5 and 6. They found lower euploidy rates with day 7 embryos and that older patients benefit less from culturing to day 7 because of increased aneuploidy, but not in the case of patients performing PGT-A.

Maternal and Neonatal Perinatal Outcomes of Singleton Pregnancies in Advanced-Age Women Undergoing IVF/ICSI-ET Compared with Spontaneous Conception: A Retrospective Propensity Score Matched Cohort Study. This study compared adverse pregnancy outcomes in women 40 and older who conceived by IVF or spontaneously. They found mostly comparable rates between the groups, but those who conceived by IVF were at higher risk of having a C-sections, with women 43 and older at higher risk of gestational diabetes and gestational hypertension.

Week 5 (Nov 26 – Dec 2)

The composition of commercially available human embryo culture media. This study analyzed the composition of commercial human embryo culture media from seven suppliers, revealing significant differences among brands despite some common trends, indicating a lack of standardization in formulations.

The impact of Duostim protocol on pregnancy outcomes in infertile patients: A meta-analysis comparing single and double conventional stimulation cycles. This meta-analysis combined the results of 6 randomized controlled trials (high quality studies) investigating the use of DuoStim, a strategy involving two ovarian stimulation cycles within a single menstrual cycle. They found significant increases the the total number of eggs and mature eggs retrieved, but no improvements in pregnancy and live birth rates.

Empirical use of growth hormone in IVF is useless: the largest randomized controlled trial. In a randomized controlled trial (high quality study), researchers investigated the use of growth hormone administered during ovarian stimulation on IVF outcomes. They found no differences in the number of follicles, retrieved eggs, mature eggs, fertilization or good quality embryo rate. There were also no differences in pregnancy outcomes.

In Vitro Fertilization induces reproductive changes in male mouse offspring and has multigenerational effects. This study used a mouse model to explore the effects of IVF on the male reproductive system, observing consistent abnormalities in testicular morphology, hormone levels, gene expression and DNA methylation across different developmental stages in IVF male offspring. Additionally, these male offspring transmitted defects to their progeny, indicating potential multigenerational impacts of IVF on reproductive and metabolic health.

Impact of Microfluidic Sperm Sorting on Embryonic Euploidy in Infertile Patients with Sperm DNA Damage: A Retrospective Study. This study found that semen samples with normal DNA fragmentation or those processed using the Zymot showed higher fertilization and euploidy rates. It concluded that high DNA fragmentation decreases fertility outcomes, but the use of the Zymot device can improve these outcomes, particularly in couples where the female partner is under 35 years old.

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About Embryoman

Embryoman (Sean Lauber) is a former embryologist and the founder of Remembryo, an IVF research and fertility education website. After working in an IVF lab in the US, he returned to Canada and now focuses on making fertility research more accessible. He holds a Master’s in Immunology and launched Remembryo in 2018 to help patients and professionals make sense of IVF research. Sean shares weekly study updates on Facebook, Instagram, and Reddit regularly. He also answers questions on Reddit or in his private Facebook group.

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