The efficiency of low-dose letrozole plus clomiphene citrate for ovulation induction in intrauterine insemination cycles: Arandomized clinical trial.

Abstract

To investigate if combination therapy with clomiphene citrate (CC) plus letrozole (L) was associated with a higher efficacy than L and CC alone in patients undergoing ovarian induction plus intrauterine insemination. The present multicenter randomized controlled clinical trial was performed between 2018 and 2020. Participants were randomized into three groups: L (n=167; 5mg/day), CC (n=167; 100mg/day), and L+CC (n=167) (2.5mg/day+50mg/day) from day 3. Ovarian stimulation was continued with the appropriate dose of gonadotropins daily starting from day 8 and continued until follicular size was 20mm or more followed by administration of human chorionic gonadotropin (10000IU). Semen samples were prepared by direct swim-up technique. In the CC group, gonadotropin dose was significantly higher but endometrial thickness was significantly lower compared with other groups. Number of follicles of 18mm or more was significantly lower in the L group compared with the other two groups. Number of follicles less than 15mm was meaningfully higher in the CC group compared with the other groups. In the L+CC group, total and largest follicular size, and the rates of chemical, clinical, and ongoing pregnancy, and live birth were significantly higher compared with other groups. Combination therapy with L+CC was superior to either L or CC for achieving pregnancy in women undergoing ovarian induction plus intrauterine insemination.