Patients
We performed a retrospective study on women who were first treated at the Reproductive Medicine Center of Tongji Hospital from January 1, 2014, to December 31, 2017. This was a non-interventional, single-center cohort study of patients undergoing routine long gonadotropin-releasing hormone (GnRH) agonist protocol. Patient information was anonymous without any identifier at the time of retrospective chart review.
BMI was expressed as the weight in kilograms divided by the square of the height in meters (kg/m2). Based on the World Health Organization classification, all patients with normal (18.5–24.9 kg/m2) and high (≥ 25 kg/m2) BMI who underwent their first fresh IVF/ICSI cycles were included in the analysis. Moreover, women with polycystic ovary syndrome (PCOS) or uterine factors such as intrauterine adhesion and mediastinum uterus were excluded, and all cycles with IVF+ICSI fertilization, donor oocyte, freeze eggs, and preimplantation genetic diagnosis/preimplantation genetic screening were not included. Finally, a total of 7701 women were enrolled and were followed up to May 2020, until either delivery of one live infant or discontinuation of treatment. A total of 464 patients did not achieve live birth but had frozen embryos from the first stimulation, and eight women were pregnant. Finally, 7229 women completed the follow-up (Fig. S1).