Natural cycle versus hormone replacement therapy as endometrial preparation in ovulatory women undergoing frozen-thawed embryo transfer: The COMPETE open-label randomized controlled trial

作者：Xitong Liu, Wentao Li, Wen Wen, Ting Wang, Tao Wang, Ting Sun, Na Zhang, Dan Pan, Jinlin Xie, Xiaojuan Liu, He Cai, Xiaofang Li, Zan Shi, Rui Wang, Na Lü, Haiyan Bai, Rong Pan, Li Tian, Bin Meng, Xin Mu, Hongran Jia, Hanying Zhou, Xu Cao, Tianxing Liu, Pengfei Qu, Danmeng Liu, Ben W. Mol, Juanzi Shi · 发表于：PLoS Medicine · 年份：2025 · DOI：10.1371/journal.pmed.1004630 · 被引用次数：22 · 研究领域：Ovarian function and disorders、Reproductive System and Pregnancy、Gynecological conditions and treatments

BACKGROUND: Different endometrial preparation protocols are used prior to frozen-thawed embryo transfer (FET). Optimization of endometrial preparation protocols is mandatory to improve live birth rate and obstetric and perinatal outcomes. In the Comparison of Endometrial Preparation Protocols for Frozen Embryo Transfer (COMPETE) trial, our primary objective is to evaluate whether natural cycles (NCs) lead to a higher live birth rate after the first FET cycle compared to hormone replacement therapy (HRT) cycles in women with a regular ovulatory cycle. METHODS AND FINDINGS: We performed a single-center, parallel, open-label randomized controlled trial between December 2020 and December 2022 in a single assisted reproduction center in Xi'an, China. Women with a regular menstrual cycle undergoing in vitro fertilization (IVF) scheduled for FET were randomly assigned (1:1) to endometrial preparation in the NC or with HRT, using a web-based electronic data capture system. The primary outcome was live birth rate after the initial FET. The analysis was conducted based on the intention-to-treat principle. Obstetric and perinatal outcomes in all randomly assigned women were reported in this study. We randomly assigned 902 women to receive either NC (n = 448) or HRT (n = 454). In the NC group, 101 women received HRT because of no ovulation, while in the HRT group, 29 women received NC because of spontaneous ovulation. The number of live births was 242 (54.0%) in the NC group versus 195 (...