Security of gonadotropin-releasing hormone antagonist protocol in patients with polycystic ovary syndrome undergoing in vitro fertilization

Objective To explore the feasibility and security of the gonadotropin-releasing hormone antagonist (GnRH-A) protocol and the prevention methods of the moderate-severe ovarian hyperstimulation syndrome (OHSS) in polycystic ovary syndrome (PCOS) patients. Methods The clinical data of 304 oocyte retrieval cycles undergoing GnRH-A protocol in PCOS patients were retrospectively analyzed. According to whether high risk of OHSS after oocyte retrieval, 304 oocyte retrieval cycles were divided into low risk of OHSS group (group A, 197 cycles) and high risk of OHSS group (group B, 93 cycles). We analyzed the basic characteristic, the initial and total dosage of gonadotropin (Gn) used, the duration of Gn used, the number of retrieved oocytes, rate of high-quality embryos, clinical pregnancy rate, the incidence of OHSS, etc. Results The high risk of OHSS was related to high basic luteinizing hormone (LH), high ratio of LH and follicle-stimulating hormone (LH/FSH) and high level of testosterone (T), when there were no statistical significances in ages, basic mass index (BMI), and the duration of infertility among patients with PCOS (P>0.05). Group A was treated with fresh embryo transfer, and the clinical pregnancy rate was 58.89% (106/197). Group B was treated with all embryos vitrified, and the clinical pregnancy rate of first frozen-thawed embryo transfer cycle was 81.81% (72/88). Comparing the two groups, there was a positive relation between the ovarian reactivity and LH/FSH on the initial day of Gn used. Overall, the accidence rate of moderate-severe OHSS was 6.91% (21/304). The moderate-severe OHSS in group A was mainly delayed type, which was related to singleton or multiple pregnancy. While the moderate-severe OHSS in group B was mainly early-onset type. Conclusion Reducing the initial dose of Gn used, assessing the properly occurrence rate of OHSS before fresh embryo transferation, GnRH-A protocol is suitable and secure for PCOS population. Patients with high risk of OHSS should select all embryos vitrified, and expect frozen-thawed embryo transfer. Key words: Gonadotropin-releasing hormone antagonist (GnRH-A); Polycystic ovary syndrome (PCOS); In vitro fertilization (IVF); Ovarian hyperstimulation syndrome (OHSS)