Comparison of the outcomes of <i>in vitro</i> fertilization and embryo transfer among ethnic Chinese Yi and Han women: a multicenter retrospective cohort study

Background: fertilization and embryo transfer (IVF-ET) is different between ethnic Yi and Han Chinese women. Methods: A total of 22,450 Han and 863 Yi women aged 20~45 years undergoing the first cycle of IVF-ET at three tertiary hospitals were retrospectively enrolled in this study. The protocols of ovarian stimulation were gonadotropin-releasing hormone (GnRH) agonist and GnRH antagonist, and the primary outcome was LBR. To minimize the influence of confounding factors, 1:1 propensity score matching (PSM) analysis was carried out before the outcomes of IVF-ET were analyzed. This clinical trial was registered with the Chinese Clinical Trial Registry (Registration number: ChiCTR2300070269). Results: < 0.05). Conclusions: The outcomes of IVF-ET were worse in Yi women compared to Han women. Ethnicity and age are associated with LBR. Maintaining a normal weight may be beneficial for LBR, especially for ethnic Han Chinese women.