Pregnancy Achievement Using Letrozole Versus Clomiphene Citrate in Anovulatory Women

Abstract

Objective: To compare pregnancy achievement using letrozole versus clomiphene citrate among anovulatory women presenting with infertility. Method: This comparative analytical study included 160 anovulatory infertile women divided equally into two treatment groups: letrozole (n = 80) and clomiphene citrate (n = 80). Baseline demographic, reproductive, endocrine, ultrasound, follicular, ovulatory, and pregnancy variables were analyzed. The primary outcome was pregnancy achievement. Secondary outcomes included mature follicle development, ovulation, biochemical pregnancy, clinical pregnancy, endometrial thickness, miscarriage, multiple pregnancy, and adverse effects. Independent samples t tests were applied for continuous variables, and chi-square tests were used for categorical variables. Results: Pregnancy was achieved in 27 women (33.8%) receiving letrozole compared with 9 women (11.3%) receiving clomiphene citrate, showing a statistically significant difference (p = .001). Letrozole was associated with higher odds of pregnancy achievement (OR = 4.02, 95% CI [1.75, 9.25]) and a higher relative probability of pregnancy (RR = 3.00, 95% CI [1.51, 5.97]). Ovulation was achieved in 63 women (78.8%) in the letrozole group and 50 women (62.5%) in the clomiphene citrate group (p = .037). Mean dominant follicle size and endometrial thickness were also significantly greater in the letrozole group. Conclusion: Letrozole was superior to clomiphene citrate for pregnancy achievement and ovulation among anovulatory infertile women in this dataset. These findings support the use of letrozole as an effective first-line oral ovulation induction option in appropriately selected women after exclusion of other infertility factors.