Controlled ovarian stimulation (COS) for FIV increases progesterone (P) and estradiol (E2) serum levels in supraphysiologic concentrations at the end of follicular phase. Elevated serum P levels leads to an accelerated endometrial maturation which interferes with the dialogue between embryo and endometrium. It has been reported that serum progesterone levels ≥ 1.5 ng/ml on the last day of COS are related to a significant decrease in the ongoing pregnancy rate following IVF cycles. Also, it has been reported a significant alteration in the endometrial gene expression profile related to P elevated levels.~Glycodelin-A is an immunomodulatory glycoprotein synthesized by luteal-phase endometrial epithelium and its expression seems to be related to the action of P. Because glycodelin-A has immunosuppressive activity, it may facilitate the process of implantation and the maintenance of pregnancy.~Objective: to evaluate the endometrial effect of Progesterone through Glycodelin-A expression pattern on women exposed or not to ulipristal acetate in GnRH Antagonist cycles using two different doses of FSH for ovarian controlled stimulation.~Methods: prospective controlled randomized study. It will be enrolling 16 oocytes donors from Oocyte Donation Program of PROAR (a Reproductive Center of Rosario, Argentina). On day 3 of menstrual cycle FSH serum levels and antral follicular count (AFC) will be measure. If those results fulfill with inclusions criteria, patients will be randomize for FSH 225UI or 300UI GnRH-Antagonist/ urinary FSH protocol. P serum levels will be measure every 48 hours since at least 1 follicle ≥14 mm will be achieve until at least 1 follicle reach 19mm of diameter. The next day of hCG administration a new P circulating will be measure and then the patient will be randomize trough opaque envelopes for receive 30mg of ulipristal acetate or placebo. An endometrial biopsy with Cornier´s Pipelle will be performing 3 and 5 days after hCG injection (hCG+3 and hCG+5 days) to evaluate endometrial dating and Glycodelin-A expression pattern.~Statistical analysis: nominal variables will be analyzing using t-Student test and the effect of ulipristal with ANOVA.
Controlled ovarian stimulation (COS) for FIV increases progesterone (P) and estradiol (E2) serum levels in supraphysiologic concentrations at the end of follicular phase. Elevated serum P levels leads to an accelerated endometrial maturation which interferes with the dialogue between embryo and endometrium. It has been reported that serum progesterone levels ≥ 1.5 ng/ml on the last day of COS are related to a significant decrease in the ongoing pregnancy rate following IVF cycles. Also, it has been reported a significant alteration in the endometrial gene expression profile related to P elevated levels.~Glycodelin-A is an immunomodulatory glycoprotein synthesized by luteal-phase endometrial epithelium and its expression seems to be related to the action of P. Because glycodelin-A has immunosuppressive activity, it may facilitate the process of implantation and the maintenance of pregnancy.~It is already know that ulipristal acetate (UPA) decrease serum P levels. The hypothesis of this study is that UPA is been able to modify P serum levels and glycodelin-A endometrial expression pattern on FSH/GnRH Antagonist cycles for FIV.