ObjectiveThe primary objective of the study was to assess traditional Chinese formula DKP supplementation in terms of efficacy and safety on reproductive outcomes of expected poor ovarian responder (POR, POSEIDON Group 4) undergoing in vitro fertilization-embryo transfer (IVF-ET).Design, Setting, and ParticipantsWomen eligible for IVF-ET were invited to participate in this randomized, double-blind, placebo-controlled, superiority trial at academic fertility centers of ten public hospitals in Chinese Mainland. A total of 462 patients (35–44 years) equally divided between DKP and placebo groups with antral follicle count (AFC)