Ultrasonographic comparative study between letrazole and clomiphene citrate on endometrial receptivity during induced ovulation

Background: Infertility is a prevalent concern affecting numerous couples worldwide, often caused by anovulation or irregular ovulation. Induced ovulation using pharmacological agents, such as letrozole and clomiphene citrate, is a commonly employed approach to enhance fertility. However, the impact of these medications on endometrial receptivity, a critical factor for successful implantation and pregnancy, remains an area of ongoing research. The primary goal of this research was to compare endometrial receptivity during induced ovulation by letrazole or clomiphene citrate. Methods: This study was prospective comparative research where 120 PCO and infertility more than 1-year women were included and divided into 2 groups: Group A (Clomid induction group) (odd numbers); Clomid was administered in 100 mg/day for 5 days dose starting from day 3 to day 7. In this group, 130 women were followed and only 60 women were included, and 70 women were excluded because either data loss or failed ovulation. Group B (Letrozole induction group) (even numbers); Letrozole was given in the dose of 5 mg/day for 5 days starting from day 3 to day 7. In this group, 90 women were followed, and 60 women were included, and 30 women were excluded because either data loss or failed ovulation. Results: The results demonstrate significant differences in endometrial thickness among the two groups. On the 11th day of the cycle, Group B exhibited a significantly higher endometrial thickness (9.82 ± 0.21 mm) compared to Group A (7.00 ± 0.21 mm) (T = -73.53, p < 0.0001). Similarly, at the stage of mature follicle (follicle > 18mm), Group B showed a significantly greater endometrial thickness (10.22 ± 0.20 mm) compared to Group A (7.49 ± 0.20 mm) (T = -73.49, p < 0.0001). Furthermore, even 7 days after ovulation, Group B maintained a significantly thicker endometrium (10.65 ± 0.22 mm) compared to Group A (7.81 ± 0.20 mm) (T = -74.33, p < 0.0001). Conclusions: Letrozole induces a greater rise in endometrial thickness and conception rate than Clomiphene citrate in infertile PCOS women. Letrozole may enhance fertility by increasing endometrial receptivity relative to CC.