Abstract:Objective To investigate the effect of basal luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratio on pregnancy outcomes of patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization-embryo transfer (IVF-ET). Methods A total of 136 PCOS patients received IVF-ET with gonadotropin-releasing hormone (GnRH) antagonist protocol at Affiliated Hospital of Shandong University of Chinese Medicine from June 2018 to June 2020 were analyzed retrospectively.According to the basal LH/FSH ratio,the patients were divided into group A (LH/FSH<1),group B (1≤LH/FSH<2) and group C (LH/FSH≥2).The influences of different basal LH/FSH ratio on ovulation induction drugs,laboratory results of embryo and pregnancy outcome were analyzed in three groups. Results There were significant differences in BMI and total dosage of gonadotropin (Gn) among three groups (group A>group B>group C,P<0.01).There was no significant difference in the number of eggs retrieved,fertilization rate,high-quality embryo rate and clinical pregnancy rate among the three groups(P>0.05). Conclusion With the decrease of LH/FSH ratio in PCOS patients,BMI and Gn dosage increased,and the patients with lower LH/FSH ratio tend to achieve better clinical outcomes of IVF-ET treatment.