Received November 13, 2022
Accepted November 13, 2023

Objectives: To evaluate the efficacy of sublingually administered human chorionic gonadotropin (HCG) in combination with clomiphene citrate (CC) or letrozole (LTZ) for ovulation induction. Methodology: In this prospective, double-blind, randomized study, patients were divided into two placebo groups and two intervention groups using CC, LTZ, and HCG. Results: No statistically significant differences in ovulation induction were observed between groups. We compared endometrial thickness at the beginning of the cycle and during the pre-ovulatory period and detected a moderate positive correlation when CC was administered with HCG. Conclusion: Sublingual HCG associated with CC led to a moderate positive correlation with endometrial thickening when compared with that at the beginning of the cycle and during the pre-ovulatory period. There was no significant change in the number of pre-ovulatory follicles.