Does pre-treatment with micronized progesterone affect the ovarian response to a gonadotropin releasing hormone agonist flare-up protocol?

The purpose of this study was to investigate the ovarian response and the receptivity of the endometrium in women pre-treated with micronized progesterone. Eighty-two normogonodotropic women undergoing in vitro fertilization were studied. Thirty received micronized progesterone 1500 mg/day from day 21 of the cycle for a minimum of 2 weeks ,and 52 did not receive micronized progesterone (control group). A gonadotropin releasing hormone agonist (GnRH-a) was administered to all the patients in the follicular phase (flare-up). Twenty-five cycles were cancelled for fertilization failure due to male factor, 12 (40%) in the progesterone group and 13 (25%) in the control group (p = 0.271). There was no difference in the number of oocytes retrieved (7.3 ± 5 vs. 8.2 ± 4) ,fertilization rate (50.8% vs. 65%) ,clinical pregnancy rate (16.6% vs. 25%) or implantation rate (8% vs. 14%). In the progesterone group cases without fertilization ,we performed two biopsies to evaluate the receptivity of the endometrium. Pinopod...