Polycystic ovary syndrome (PCOS) is a common cause of anovulatory infertility and is associated with an increased risk of premature luteinizing hormone (LH) surges during controlled ovarian stimulation. Progestin-primed ovarian stimulation (PPOS) using Medroxyprogesterone Acetate (MPA) has emerged as a convenient alternative to conventional gonadotropin-releasing hormone (GnRH) antagonist protocols. This study aimed to compare the effects of MPA-based PPOS and GnRH antagonist protocols on oocyte yield, maturation, fertilization, and embryo quality in women with PCOS undergoing ICSI . This prospective, randomized, open-label controlled clinical trial included 108 women with PCOS undergoing ICSI at the High Institute for Infertility Diagnosis and Assisted Reproductive Technologies, Al-Nahrain University, Baghdad, Iraq, between 2023 and 2024. Participants were allocated to an MPA-based PPOS group (n=49) or a flexible GnRH antagonist group (n=59). Oocyte yield, metaphase II (MII) oocytes, fertilization rate, embryo quality, ovarian sensitivity index (OSI), gonadotropin consumption, stimulation duration, and LH profiles were evaluated.No significant differences were observed in baseline characteristics or hormonal profiles between groups. The MPA group showed a numerically higher number of retrieved oocytes (20.65 ± 7.50 vs. 13.39 ± 4.41; p=0.083) and MII oocytes (15.10 ± 5.20 vs. 11.24 ± 4.12; p=0.09), although these differences were not statistically significant. Fertilization rates were comparable between groups (72.4 ± 10.6% vs. 71.2 ± 11.3%; p=0.68), as were embryo quality, OSI, gonadotropin consumption, and stimulation duration. Both protocols effectively suppressed premature LH surges without premature ovulation or cycle cancellation. MPA-based PPOS appears to be an effective and practical alternative to GnRH antagonist protocols for PCOS patients undergoing ICSI, providing comparable fertilization and embryological outcomes with effective LH suppression. Its oral administration and potential cost advantages may be particularly valuable in resource- limited ART settings.