Progestin-primed ovarian stimulation vs mild stimulation in women with advanced age above 40: a retrospective cohort study

Background Previous studies have demonstrated that progestin-primed ovarian stimulation (PPOS) protocol was a feasible and efficient method in in vitro fertilization (IVF) cycle. However, its application in women with advanced age has not been determined yet. The purpose of this study was to investigate its efficacy in women aged ≥40 years old.