Clinical Pregnancy Outcomes of Gonadotropin-Releasing Hormone Agonist in Intrauterine Insemination Cycles for Unexplained Infertility: A Randomized Controlled Trial

Background & Objective: This study aimed to evaluate the effectiveness of a GnRH agonist in Intrauterine Insemination (IUI) cycles among women with unexplained infertility.Materials & Methods: A randomized, open-label clinical trial was conducted at two infertility treatment centers in Tashkent, Uzbekistan from April to November 2025. A total of 180 women diagnosed with unexplained infertility was randomly assigned in equal numbers to two study groups. Final oocyte triggering with the hCG was performed once the leading follicle reached a diameter of 18 mm, followed by IUI 36-40 hours later.Results: Of the 180 enrolled participants, 164 underwent insemination. The clinical pregnancy rate did not differ significantly between the GnRH agonist group and the control group (22.3% vs 13.7%; P=0.15). However, significant differences were observed in the number of follicles≥14 mm (2.6 vs 1.9; P<0.001) and in endometrial thickness at the time of triggering (9.8 vs 8.2 mm; P<0.001). Subgroup analyses indicated that the GnRH agonist provided greater benefit for women aged ≥35 years (P=0.04) and for those with a BMI<25 kg/m² (P=0.03).Conclusion: Considering its acceptable safety profile and minimal side effects, the GnRH agonist may serve as an effective treatment option for women undergoing IUI for unexplained infertility. Larger multicenter trials are recommended to validate these findings.