摘要:Recurrent implantation failure (RIF) brings great challenges to clinicians and causes deep frustration to patients. Previous data has suggested that prednisone may play a promising role in the establishment of pregnancy and help improve the pregnancy outcome in women with RIF. But there is insufficient evidence from randomized clinical trials that had adequate power to determine if prednisone can enhance live births as the primary outcome. This trial is a prospective, multicenter, randomized, double-blind, placebo-controlled clinical trial (1:1 ratio of prednisone versus placebo). Infertile patients with RIF who intend to undergo frozen-thawed embryo transfer (FET) after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) or pre-implantation genetic testing for aneuploidy (PGT-A) will be enrolled and randomly assigned to two parallel groups. Participants will be given the treatment of prednisone or placebo from the start of endometrial preparation till the end of the first trimester of pregnancy if pregnant. The primary outcome is live birth rate. The results of this study will provide evidence for the effect of prednisone on pregnancy outcomes in patients with RIF. Chinese Clinical Trial Registry, ChiCTR1800018783 . Registered on 9 October 2018.