Comparison of the Efficacy of Letrozole and Clomiphene Citrate for Ovulation Induction in Infertile Women with Polycystic Ovary Syndrome

Aim: To compare the efficacy of letrozole with clomiphene citrate for ovulation induction in infertile patients with polycystic ovarian syndrome (PCOS). Methods: This clinical trial study was carried out at Gynae unit 2 Lady Willingdon Hospital Lahore from 1st July2012-30th June 2013. Total 100 patients of PCO were included in the study. Diagnosis of PCO was made on Rotterdam criteria. In this clinical trial, 100 infertile patients with PCOS received either 100 mg clomiphene citrate (n=50) or 2.5mg letrozole (n=50) daily since day 2-6 of their menstrual cycle. Human chorionic gonadotropin (hCG) was administered at a dose of 10,000IU when at least 1 mature follicle (17-25mm) was detected. Timed intercourse was advised to the patients after 24-36 hrs of HCG injection. Then the number of follicles, endometrial thickness, P4 on day 21, ovulation rate, and pregnancy rate were measured in both groups. Results: Monofollicular development was statistically significantly, greater in the Let group (CC 55.76%, Let 78.32%). There was no statistically significant difference between the two groups in endometrial thickness on the day of HCG injection (CC 7.62 +/- 1.95mm, Let 7.65 +/- 1.98mm P=0.91). Similarly, there was no statistically significant difference between the two groups in days to ovulation, and serum P-4 on D-21. The ovulation rate was 60.02% in CC group and 72.28% in Let group. The pregnancy rate was in 7.42% CC group and 20.55% in Let group. There was one multiple pregnancy in cc group. Conclusion: Letrozole might be an acceptable alternative to clomiphene citrate to induce ovulation and pregnancy in PCOS patients.