Objective: To compare two different gonadotropin preparations, human menopausal gonadotropin (hMG) and recombinant follicle-stimulating hormone (rFSH), combined with clomiphene citrate (CC) in women with unexplained infertility undergoing intrauterine insemination (IUI).

Study design: In this prospective clinical trial, couples prepared for IUI cycles were randomly allocated to two groups either to receive CC and hMG (group A, n=127) or CC and rFSH (group B, n=132) for ovarian stimulation. Outcomes including rates of clinical pregnancy, miscarriage, OHSS, multiple pregnancy, cancellation, and live birth were compared between groups.

Results: Duration of gonadotropin therapy was significantly shorter in group B (5.1±0.84 vs. 4.7±0.8 days, CI=95%, P<0.001). The total dose of administered gonadotropin was also significantly lower in group B (386.9±68.2 vs. 348.2±56.3IU, CI=95%, P<0.001). Dominant follicle number (>17mm), mean follicular diameter, and endometrial thickness on the day of hCG injection were similar. Clinical pregnancy, multiple pregnancies, abortion, live birth, ovarian hyperstimulation syndrome (OHSS), and cancellation rates were not statistically different between the groups.

Conclusion: IUI cycles in which rFSH had been administered may require shorter duration and a lower total gonadotropin dose.