A new study from Michigan State University, the largest of its kind, seems to indicate that there may be such a thing as too much of a good thing when it comes to hormones, in particular follicle stimulating hormone (FSH) and fertility.
Researchers looked at a total of 658,519 fresh autologous cycles of in vitro fertilization (IVF) that had been reported to the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System (SART CORS) from 2004 to 2012. Logistic regression models were fitted to live birth rates with the use of values for total FSH dose and the number of oocytes retrieved. To reduce the potential significant confounders, additional analyses were restricted to patients with a good prognosis (<35 years of age, body mass index <30 kg/m2, and no diagnosis of diminished ovarian reserve, endometriosis, or ovulatory disorder) and duration of gonadotropin treatment was included.
Regardless of the number of oocytes retrieved, the live birth rate significantly decreased as the FSH dose increased, reaching as much as 15% to 20%. The significant decrease in live birth was seen even in patients with a good prognosis, regardless of age, except for women aged ≥35 years with 1–5 oocytes retrieved.
The investigators noted that some of the cycles studied may have been in women with diminished ovarian reserve even though the diagnosis was not reported by the IVF program. SART CORS also does not contain information on antral follicle count. Therefore, this analysis does not reflect some of the predictors of ovarian sensitivity that physicians may use to determine FSH dosage.
Nevertheless, the authors concluded that physicians may want to avoid prescribing high doses of FSH. They said, however, that the study results should in no way be read as justification for minimal-stimulation or natural-cycle IVF.
Why progesterone may not be answer in recurrent pregnancy loss
Use of progesterone supplements started in the first trimester of pregnancy do not improve pregnancy outcomes in women with a history of unexplained recurrent miscarriage, according to a new randomized trial from the University of Birmingham in the United Kingdom.
The researchers assessed 1568 women with a history of unexplained recurrent miscarriage for eligibility and selected 836 women who conceived naturally within a year and were willing to participate in the trial. They were randomized to either twice-daily vaginal suppositories containing 400 micronized progesterone (404 women) or a matched placebo (432 women) given from soon after a positive urinary pregnancy test and no later than 6 weeks’ gestation through 12 weeks’ gestation.
The primary outcome was live birth at more than 24 weeks’ gestation.
Overall the follow-up rate for the primary outcome was 98.8% (826 of 836 women). Based on an intention-to-treat analysis, the rate of live birth was 65.8% (262 of 398 women) in the progesterone group and 63.3% (271 of 428 of 428 women) in the placebo group (relative rate 1.04, 95% confidence interval [CI], 0.94 to 1.15). No significant between-group differences were seen in the rate of adverse events.
The investigators concluded that use of progesterone therapy over the course of the first trimester did not significantly improve the live birth rate when compared to no treatment.