Currently, controlled ovarian stimulation (COS) in oocyte donors is performed by daily injections of gonadotropins( recombinant FSH) plus a GnRH Antagonist usually form 5th-6th stimulation day until ovulation induction with a bolus of another injection of a gonadotropin-releasing hormone (GnRH) Agonist. Injections of the GnRH Antagonist avoid untimely luteinizing hormone (LH) surge and spontaneous ovulation prior to follicular aspiration. There is a preparation of long-acting recombinant follicle stimulating hormone (rFSH= (corifollitropin alfa (FSH-CTP), Elonva®, MSD), that allows that a single subcutaneous injection substitutes the first 7 days of daily gonadotropin injections. On the other hand, a contraceptive oral progesterone only( Desogestrel, DSG) is available for contraception, avoiding the LH surge. It has been described the usefulness of orally administered medroxyprogesterone acetate, 10 mg to inhibit the endogenous LH surge in IVF patients during COS.