A personalized medicine approach to ovulation induction/ovarian stimulation: development of a predictive model and online calculator from level-I evidence

New Belgian legislation regarding the limitation of transferable embryos in in vitro fertilization cycles does not significantly influence the pregnancy rate but reduces the multiple pregnancy rate in a threefold way in the Leuven University Fertility Center

What is the effect of small follicles on clinical pregnancy and multiple pregnancy rates in women undergoing IUI with ovarian stimulation (IUI-OS)? The presence of ≥2 small follicles with a diameter of 10-12 or 12-14 mm was associated with an increased chance of clinical pregnancy and the presence of any 12-14 mm or larger follicles, but not smaller follicles, was statistically significantly associated with an increased risk for multiple pregnancy. IUI-OS is widely used as the first-line treatment for unexplained or mild male factor infertility. However, IUI is associated with the risk of multiple pregnancy. While the positive association between the number of follicles ≥14 mm and the chance of pregnancy and the risk of multiple pregnancy is known, the impact of smaller follicles is uncertain. This was a retrospective cohort study that included women undergoing IUI cycles from January 2007 to May 2021 in one assisted reproduction center. We studied the impact of the number and size of follicles on trigger day on clinical pregnancy and multiple pregnancy rates. Generalized estimation equation regression models were used to compute unadjusted and adjusted odds ratios and 95% CI in all women and only women who achieved clinical pregnancy separately. The chance of clinical pregnancy and multiple pregnancy for different numbers of small follicles in cycles with one >18-mm follicle was calculated using marginal effects estimate. This cohort included 12933 IUI cycles in 7504 women. The overall clinical pregnancy rate was 16.1% (2081/12933), with a multiple pregnancy rate of 10.5% (218/2081). In the adjusted analysis, the chance of clinical pregnancy increased significantly with the increase in the number of follicles with the diameter of 14-16, 16-18, and 18-20 mm. As for 10-12 mm [adjusted odds ratio (aOR) 1.22, 95% CI 1.02-1.46] and 12-14 mm (aOR 1.29, 95% CI 1.07-1.56) follicles, only groups with ≥2 follicles of those sizes showed significantly increased chance of clinical pregnancy. In cycles that led to pregnancy, follicles with the diameter of 12-14 mm were associated with an increased risk of multiple pregnancy (aOR 1.73, 95% CI 1.19-2.53 for one such follicle; aOR 2.27, 95% CI 1.44-3.56 for ≥2 such follicles), while 10- to 12-mm follicles were not significantly associated with multiple pregnancy (aOR 1.18, 95% CI 0.72-1.95 for ≥2 such follicles). The associations of multiple pregnancy were similar when including all cycles. This was a retrospective observational study from a single center. The records of follicle diameter in our center were of a 2-mm interval which limited our ability to analyze the size of follicle as a continuous variable. Also, the number of cycles with a high number of small follicles was still limited which impeded more detailed analysis on the ≥2 follicles subgroup. Similarly, the value of some parts of the marginal probability estimation for multiple pregnancy versus pregnancy according to size and number of follicles was also limited by the low sample size of certain combinations. Follicles larger than 10 mm, especially those ≥12 mm, may need to be clearly recorded during transvaginal ultrasound surveillance and their potential effects on both pregnancy and multiple pregnancy can be discussed with couples undergoing IUI. This work was supported by the National Natural Science Foundation of China (Grant numbers 82201912, 82371651, and 82071615) and Shanghai Sailing Program (21YF1423200). B.W.M. is supported by an NHMRC Investigator grant (GNT1176437). B.W.M. reports consultancy for ObsEva and Merck and travel support from Merck. B.W.M. has received research funding from Ferring and Merck. The authors declare no other competing interests. N/A.

Elective single-embryo transfer in oocyte donation programmes: should it be the rule?

Cetrorelix lowers premature luteinization rate in gonadotropin ovulation induction–intrauterine insemination cycles: a randomized-controlled clinical trial

Letrozole appears to improve live birth rates and pregnancy rates in infertile women with anovulatory PCOS, compared to SERMs, when used for ovulation induction, followed by intercourse. There is high-certainty evidence that OHSS rates are similar with letrozole or SERMs. There was high-certainty evidence of no difference in miscarriage rate and multiple pregnancy rate. We are uncertain if letrozole increases live birth rates compared to LOD. In this update, we added good quality trials and removed trials with concerns over data validity, thereby upgrading the certainty of the evidence base.

Pretreatment with oral contraceptives in infertile anovulatory patients with polycystic ovary syndrome who receive gonadotropins for controlled ovarian stimulation

Letrozole induction of ovulation in women with clomiphene citrate–resistant polycystic ovary syndrome may not depend on the period of infertility, the body mass index, or the luteinizing hormone/follicle-stimulating hormone ratio

In vitro maturation and fertilization of oocytes from unstimulated ovaries in infertile women with polycystic ovary syndrome

Rapid policy change to single-embryo transfer while maintaining pregnancy rates per initiated cycle

We found evidence suggesting that clomiphene citrate improves the chance of a clinical pregnancy compared with placebo, but may reduce the chance of live birth or ongoing pregnancy when compared with a gonadotropin. Due to low event rates, we advise caution interpreting these data.The comparison of clomiphene citrate plus medical adjunctive versus clomiphene alone was limited by the number of trials reporting the comparison. The evidence was very low quality and no firm conclusions could be drawn, but very limited evidence suggested a benefit from adjunctive dexamethasone or combined oral contraceptives. Low-quality evidence suggested that a 10-day regimen of clomiphene citrate improves pregnancy rates compared with a 5-day regimen, but further research is required.

Gonadotropin-releasing hormone agonist to induce final oocyte maturation prevents the development of ovarian hyperstimulation syndrome in high-risk patients and leads to improved clinical outcomes compared with coasting

Single instead of double day-five blastocyst transfer maintains the same clinical pregnancy rate and decreases multiple pregnancy and abortion rates in fresh IVF cycles

In this review, there was very low-quality evidence to show that taking an antioxidant may provide benefit for subfertile women, but insufficient evidence to draw any conclusions about adverse events. At this time, there is limited evidence in support of supplemental oral antioxidants for subfertile women.

Recombinant FSH increases live birth rates as compared to clomiphene citrate in intrauterine insemination cycles in couples with subfertility: a prospective randomized study

Continuous quality improvement and assisted reproductive technology multiple gestations: some progress, some answers, more questions