GnRh Antagonist Protocol With Delayed Start Stimulation in Patients With Poor Ovarian Response

The main outcome measures are the number of dominant follicles (≥13 mm) on the day of hCG trigger and the number of mature (MII) oocytes collected after conventional versus delayed-start ovarian stimulation protocol. Secondary outcome measures are including total number of oocytes retrieved, oocyte maturity rate (number of MII oocytes/total number of oocytes), oocyte yield (total number of oocytes retrieved/ antral follicle count \[AFC\]), mature oocyte yield (number of mature oocytes retrieved/AFC), total dosage of gonadotropin (recombinant FSH and/or highly purified hMG) needed, number of days needed for ovarian stimulation, quality of obtained embryos, fertilization rate (the proportion of total number of two-pronuclear \[2PN\] stage zygotes /per total injected MII oocytes), implantation rate (total number of observed gestational sac/ number of transferred embryos) and clinical pregnancy rate (presence of fetal heart beat by transvaginal ultrasound per embryo transfer).