Clomiphene citrate vs Letrozole as first line ovulation induction drug in infertile PCOS women : Research Article

Elmahaishi MS

doi:10.58372/2835-6276.1188

Authors

Elmahaishi MS

DOI:

https://doi.org/10.58372/2835-6276.1188

Keywords:

Clomiphene citrate , Letrozole , infertile PCOS women

Abstract

Background: Polycystic ovary syndrome (PCOS) is the commonest endocrinopathy resulting in anovulatory infertility in young women as in recent years have seen a significant rise in women presenting with PCOS . Despite wide acceptance of clomiphene citrate (CC) as the first-line drug for ovulation induction in women with polycystic ovaries (PCOS), a significant proportion of women do not respond to this treatment. In addition, CC use is known to have several disadvantages, including a discrepancy between ovulation and conception rates. Recent studies have suggested that letrozole, an aromatase inhibitor, can be used for ovulation induction and is associated with higher pregnancy rates and less complications than CC treatment in women with PCOs.

Aim of study: To compare the efficacy of letrozole and clomiphene citrate (CC) for ovulation induction in infertile women with polycystic ovarian syndrome (PCOS).

Materials and methods: The prospective randomized trial was conducted between February 2023 and February 2024 at Lamis IVF center in Misrata-Libya. 103 infertile PCOS patients were randomly selected for the study . All patients were selected started 5 mg letrozole (52 patients) or 100 mg clomiphene citrate (51 patients) twice daily starting day 2 to day 6 of menstrual cycle. When at least one mature follicle (with a mean diameter ≥ 18 mm) was observed, 10000 IU of human chorionic gonadotrophin (hCG) were given subcutaneously to trigger ovulation.

Results: The mean age, Body Mass Index (BMI), duration of infertility in both Clomiphene Citrate (CC) and Letrozole groups were similar. Ovulation rate was 67.3% in letrozole group and 58.8% in CC, which was not significant. There was no statistically significant difference between Endometrial thickness (CC 7.99 ±2.4, Let 8.69 ± 2.14) and days of ovulation (CC 13.6 ± 2.1; Let 13.1 ± 2.4). Mono-follicular development (CC 56.6% , Let 80 % ) and Pregnancy rate (CC 11.7%, Let 28.8% ) were significantly higher in letrozole group.

Conclusion: Letrozole is a better alternative for ovulation induction in anovulatory women with PCOS as pregnancy rates are higher and chances of multiple pregnancy are less because of high mono-follicular growth. We recommend letrozole over clomiphene citrate as an ovulation induction drug in women with infertility and PCOS, although the quality of the evidence is mixed.

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