Pregnancy outcome in long- versus short-acting gonadotropin-releasing hormone agonist cycles in participants with normal ovarian reserve: An RCT

 There is no agreement on which of the 2 gonadotropin-releasing hormone (GnRH) agonist protocols are the most efficient, neither there is any consensus on which one yields a better clinical pregnancy percentage.

 The present study aims to compare the effectiveness of reduced dosages of long- and short-acting GnRH agonists on pregnancy outcomes.

 In this randomized controlled clinical trial, 400 women were randomly assigned to 2 groups (n = 200/group): the reduced dosage of long-acting GnRH agonist group (group 1, 1.25 mg Decapeptyl) and the short-acting GnRH agonist group (group 2, 0.5 mg/day Buserelin Acetate). The study was conducted at Mehr Medical Institute, Rasht, Iran between July 2019 and July 2020. Biochemical and clinical pregnancy were compared between groups.

 No significant differences were observed in the endometrial lining, the total number of retrieved and metaphase-II oocytes, progesterone, and serum estradiol levels on human chorionic gonadotropin day, fertilization rate, and top-quality embryos between the groups. The duration of induction (10.8 ± 1.7 vs. 10 ± 2.1, p < 0.001) and the total dosage of gonadotropins (2939.4 ± 945.9 vs. 2441 ± 1247.1, p < 0.001) were significantly greater in group 2 than in group 1. No significant differences were observed between the 2 groups in terms of implantation rate, chemical pregnancy rate, and clinical pregnancy rate. A higher percentage of ovarian hyperstimulation syndrome was observed in group 2 (p = 0.005).

 Due to a lower percentage of ovarian hyperstimulation syndrome in group 1 and similar assisted reproductive technology outcomes in both groups, the long protocol was found to be superior to the short protocol.