Comparison of the efficacy of letrozole and gonadotropin combination versus gonadotropin alone in intrauterine insemination cycles in patients with unexplained infertility

This study aimed to determine the outcomes of combined treatment of letrozole (LTZ) with recombinant folliclestimulating hormone (rFSH) in comparison with rFSH alone in intrauterine insemination (IUI) cycles. This study consisted of 86 patients who experienced 106 IUI cycles. Patients were classified into two treatment groups: group I underwent a combination of LTZ plus rFSH, and group II received rFSH alone. Ovulation was triggered with human chorionic gonadotropin (hCG), and IUI performed 36 hours later. The number of foll icles >18 mm, endometrial thickness, required dose of FSH, duration of ovulation induction (OI), clinical pregnancy rates, multiple pregnancy rates, spontaneous abortion rates, and live birth rates were evaluated. The total required rFSH dose during the OI was significantly lower in the LTZ-rFSH combination group than the rFSH alone group (401.2±177.1 IU and 770.1±345.8 IU, respectively, p