Monthly IVF research brief for June 2024

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

---

Week 1 (June 4 – 10)

IVF and perinatal outcomes of advanced maternal age patients after single frozen euploid embryo transfer: a propensity-matched analysis of autologous and donor cycles. This study compared live birth rates for patients aged 39-46 who did PGT-A using donor eggs or their own eggs. They found no differences in live birth rates for euploids from donor eggs or the patient’s’ own eggs. This shows that age isn’t a factor when transferring a euploid.

Preimplantation genetic testing for aneuploidy: predictive embryonic factors. This study compared over 6,000 PGT-A cycles for euploidy and thaw survival rates. They found that excellent quality blastocysts and day 5 blastocysts were more likely to be euploid and survive the thaw compared to lower quality or day 6 blastocysts. They also found that fully hatched blastocysts had lower thaw survival rates compared to non-hatching blastocysts.

Innate and adaptive immune dysregulation in women with recurrent implantation failure. This is a review on immune dysregulation and its links to recurrent implantation failure. Although the evidence is lower quality, it discusses T cells, B cells, NK cells and macrophages, and how their dysregulation can lead to inflammation and problems with implantation.

Use of artificial intelligence embryo selection based on static images to predict first-trimester pregnancy loss. This study describes the use of the ERICA AI algorithm that assessed pictures of blastocysts and related it to miscarriage. ERICA had a classification accuracy of 67.4%.

Metabolic Profiles of Offspring Born From Biopsied Embryos from Toddlerhood to Preschool Age. This study compared the endocrine and metabolic health of over 1,200 children aged 1-5 born from euploid transfers by PGT-A. They found no adverse metabolic outcomes in these children, and no differences with children born through IVF/ICSI (without PGT-A).

Week 2 (June 11 – 17)

Double versus single stimulation in young low prognosis patients followed by a fresh embryo transfer: a randomized controlled trial (DUOSTIM-fresh). Researchers performed a high quality study (a randomized controlled trial/RCT) to compare single and double (duostim) ovarian stimulation. Duostim involves ovarian stimulation during both the follicular and luteal phase of the same cycle, with two egg retrievals. Duostim resulted in more good quality blastocysts, with about the same number of eggs retrieved in each cycle. There was no increase in the rate of cycles that had an embryo transfer or in ongoing pregnancy rates.

Minimum number of mature oocytes needed to obtain at least one euploid blastocyst according to female age in In Vitro Fertilization cycles. In this study, researchers developed a mathematical model to predict the number of mature eggs needed to get a euploid, based on female age. The accuracy of this model was 72.0%.

The ovarian stimulation regimen does not affect aneuploidy or blastocyst rate. This study compared aneuploidy and blastocyst rates in patients that received different amounts of gonadotropins during ovarian stimulation, along with pregnancy outcomes. Women with high or low gonadotropins had similar aneuploidy and blastocyst rates, with no differences in cumulative live birth rates.

Acupuncture combined with gonadotropin-releasing hormone agonists improves endometrial receptivity and pregnancy outcome in patients with recurrent implantation failure of in vitro fertilization-embryo transfer. This study compared pregnancy outcomes in RIF patients that were treated with gonadotropin-releasing hormone agonists (GnRHa) and acupuncture in preparation for an embryo transfer. Patients treated in this way had a thicker endometrium, and a higher pregnancy rate after transfer.

Effectiveness of recombinant human FSH: recombinant human LH combination treatment versus recombinant human FSH alone for assisted reproductive technology in women aged 35-40 years. This study compared outcomes in patients that received FSH with LH or FSH alone during ovarian stimulation. A combination of treatments resulted in better live birth rates, but only slightly and only in older women.

Week 3 (June 18 – June 24)

Ongoing pregnancy rates in single euploid frozen embryo transfers remain unaffected by female age: a retrospective study. This study found no differences in ongoing pregnancy rates for patients aged ≤35 to >40 who transferred a single euploid embryo (based on their age at egg retrieval). Women with good quality embryos, with a lower BMI and who had a natural cycle frozen embryo transfer (as opposed to medicated) had higher ongoing pregnancy rates.

Single day 14 serum hCG values allow prediction of viable pregnancy and are significantly higher in frozen as compared to fresh single blastocyst transfer. This study involved patients who had a single frozen or fresh blastocyst transferred, and then had a pregnancy test 14 days later (by hCG). Women who transferred a frozen embryo had higher hCG levels compared to those who had a fresh transfer, suggesting that the type of transfer needs to be considered for pregnancy monitoring.

Prospective reproductive outcomes according to sperm parameters, including DNA fragmentation, in recurrent pregnancy loss. In a small prospective cohort study, researchers followed couples with recurrent pregnancy loss and high DNA fragmentation. Couples with high DNA fragmentation had a lower chance of becoming pregnant, but there was no increased risk of experiencing another pregnancy loss.

Maternal age at transfer following autologous oocyte cryopreservation is not associated with live birth rates. This study found that maternal age didn’t influence live birth rates after patients thawed their frozen eggs and had a transfer. This suggests that it’s the age at retrieval that dictates success rates and not the age at transfer.

The role of age and AMH on cumulative live birth rates over multiple frozen-thawed embryo transfer cycles: a study based on low prognosis patients of POSEIDON 3 and 4 groups. This study compared cumulative live birth rates for patients with a poor prognosis based on POSEIDON criteria (low AMH/advanced age). POSEIDON group 1 had the highest cumulative live birth, followed by group 3, group 2 and group 4.

Week 4 (June 25 – July 1)

The impact of microfluidics sperm processing on blastocyst euploidy rates compared with density gradient centrifugation: a sibling oocyte double-blinded prospective randomized clinical trial. This randomized controlled trial (high quality study) measured euploidy and other outcomes for couples whose sperm was processed using microfluidics (Zymot) or by conventional methods (density gradient centrifugation). They found no differences in euploidy or blastocyst formation rates, but Zymot improved fertilization rates. There were no differences in pregnancy outcomes.

Unexplained infertility and age-related infertility: indistinguishable diagnostic entities but different IVF prognosis. This study investigated the links between advanced maternal age and unexplained infertility. They found that older patients were more likely to be diagnosed with unexplained infertility, and patients with unexplained infertility had lower IVF success rates compared to patients with explained infertility, even when considering age.

Do Popular Diets Impact Fertility? This review examines the effects of different diets on fertility, including the Mediterranean diet, the DASH diet, the Western diet, the ketogenic diet and the vegetarian diet.

Comparison of luteal support protocols in fresh IVF/ICSI cycles: a network meta-analysis. This meta-analysis combines the results of 27 RCTs that compare different protocols for luteal phase support after a fresh transfer, finding that certain protocols improved live birth rates and reduced miscarriage rates, particularly combinations of subcutaneous GnRH-a and vaginal progesterone.

Current recommendations for vaccines for patients planning pregnancy: a committee opinion. This is an ASRM committee opinion on the use of vaccines during pregnancy, covering vaccines that target COVID-19, influenza, tetanus, varicella, hepatitis and more. Generally, they recommend vaccination before infertility treatments start because some vaccines shouldn’t be administered during pregnancy.

If you want to get even more of the latest research each week, you can sign up for a paid subscription to Remembryo to get an upgraded weekly newsletter. Plus, you’ll be supporting me in my efforts to share the latest IVF research!

If you liked this post and want to support what I do, please consider a paid subscription, Patreon or donate through PayPal!

 

---

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.

---