Comparison of PPOS and GnRH antagonist protocols in patients undergoing PGT-A.

This study aimed to evaluate the safety and efficacy of the flexible progestin-primed ovarian stimulation (PPOS) protocol. Recently, this protocol has become increasingly popular, especially in treatment plans that require a freeze-all strategy due to the risk of ovarian hyperstimulation syndrome, preimplantation genetic testing for aneuploidy (PGT-A), or embryo cryobanking. Rather than using the conventional PPOS, we opted for a more flexible approach.