A novel orally active gonadotropin-releasing hormone antagonist, relugolix, is a potential substitute for injectable GnRH antagonists in controlled ovarian stimulation in assisted reproductive technology

Reprod Med Biol. 2021 Nov 12;21(1):e12424. doi: 10.1002/rmb2.12424. eCollection 2022 Jan.

Abstract

Purpose: To evaluate the efficacy of an oral gonadotropin-releasing hormone antagonist (GnRH Ant), relugolix (R), for assisted reproductive technology (ART).

Methods: We enrolled women undergoing ART using a GnRH Ant for controlled ovarian stimulation. We compared R; 20 mg/day with cetrorelix acetate (C); 0.125 mg. C was administered to 88 women in 2019, and R to 93 women in 2020. Clinical outcomes associated with ART were assessed in both groups.

Results: The luteinizing hormone levels on the day of human chorionic gonadotropin injection in the R group (1.26 ± 0.93 IU/L) were significantly lower than those in the C group (2.85 ± 3.02 IU/L). There were no cases in which egg retrieval was canceled in both groups. The total doses of gonadotropins administered were greater in the R group compared with the C group. The number of days of GnRH Ant administration in the R group (1.71 ± 0.57 days) was significantly longer compared with the C group (1.48 ± 0.58 days). The number of oocytes collected, fertilization rates, and pregnancy rates (R; 47.1% vs C; 45.8%) did not differ between the two groups.

Conclusion: An orally active GnRH Ant, relugolix, when used in controlled ovarian stimulation for ART, showed comparable clinical outcomes with cetrorelix.

Keywords: Gonadotropin‐releasing hormone antagonist; cetrorelix; controlled ovarian stimulation; pregnancy rate; relugolix.