Progesterone elevation does not compromise pregnancy rates in high responders: a pooled analysis of in vitro fertilization patients treated with recombinant follicle-stimulating hormone/gonadotropin-releasing hormone antagonist in six trials.

To compare the impact of elevated P during the late follicular phase on the chance of pregnancy in low, normal, and high responders. Retrospective combined analysis from six clinical trials. IVF centers. Women up to 39 years of age with a regular menstrual cycle and an indication for ovarian stimulation before IVF/intracytoplasmic sperm injection. Ovarian stimulation with recombinant (r) FSH in a GnRH antagonist protocol. Ongoing pregnancy rates (OPRs) assessed with the use of univariate and multivariate analyses according to serum P levels ≤ 1.5 ng/mL versus >1.5 ng/mL on the day of hCG administration and compared among low (1-5 oocytes), normal (6-18 oocytes), and high (>18 oocytes) responders. A total of 157/1,866 women (8.4%; 95% confidence interval [CI] 7.2%-9.8%) had elevated P. Incidence of elevated P increased from 4.5% in low responders to 19.0% in high responders. Overall, OPRs were significantly lower in women with elevated P. Per started cycle, the >1.5 to ≤ 1.5 ng/mL adjusted odds ratio was 0.55 (95% CI 0.37-0.81). OPRs were not impaired in high responders with P elevation and were significantly higher compared with normal responders with P elevation. The incidence of elevated P increases with ovarian response, and elevated P at a threshold of 1.5 ng/mL is independently associated with a decreased chance of pregnancy in low to normal responders, but not in high responders, when using an rFSH/GnRH antagonist protocol.