[The clinical effects of oral contraceptive pretreatment on the outcome of gonadotropin releasing hormone antagonist protocol in non-polycystic ovary syndrome patients].

Objective: To evaluate the clinical effect of oral contraceptive (OC) pretreatment on the outcome of gonadotropin releasing hormone antagonist (GnRH-a) protocol in patients with non-polycystic ovary syndrome. Methods: From January 2017 to May 2019, a total of 436 patients undergoing in vitro fertilization and embryo transfer/Intracytoplasmic sperm injection (IVF-ET/ICSI) treatment in Peking University First Hospital reproductive center clinic were included in this retrospective cohort study. A total of 144 patients (147 cycles) used OC pretreatment prior to GnRH-a protocol and 292 patients (306 cycles) used GnRH-a protocol without OC pretreatment. The drug usage as well as pregnant outcomes between groups were examined. The primary outcome was the cumulative clinical pregnancy rate of oocyte retrieval cycle and the secondary outcome included the number of oocytes, MⅡ oocytes, embryos and clinical pregnancy rate of fresh embryo transfer cycle. Results: The median ages (and Q1, Q3) of OC pretreatment group and non-OC group were 33 (30,36) and 34 (30,38) years old, respectively. The number of MⅡ oocytes was higher in OC pretreatment group (7/9) than in non-OC group (6/8) (P=0.002). The significant difference were not found in the cumulative clinical pregnancy rate of each oocyte retrieval cycle (61.7% vs 54.6%), the clinical pregnancy rate of fresh embryo transfer cycle (34.4% vs 35.6%), and the number of oocytes (9 vs 8) and embryos (6 vs 6) between groups. Conclusion: Our findings suggest that compared to non-OC pretreatment group, pretreatment with OC is associated with more MⅡ oocytes, and with an increasing trend of the cumulative clinical pregnancy rate in non-polycystic ovary syndrome patients undergoing fresh IVF-ET/ICSI.