COMPARISON OF LETROZOLE AND CLOMIPHENE CITRATE FOR INDUCTION OF OVULATION IN PATIENTS WITH POLYCYSTIC OVARIAN SYNDROME

BACKGROUND AND OBJECTIVE: Clomiphene citrate is the first–line treatment in patients with ovulatory dysfunction, but it may be associated with side effects for example multiple follicles, multiple pregnancy and adverse effects on endometrial growth. Nowadays, it is considered to use letrozole for induction ovulation. The aim of this study was to compare letrozole with clomiphene citrate for ovulation induction, in patients with polycystic ovarian syndrome (PCOs). METHODS: This clinical trial study was performed on 107 PCOs patients. They divided into two groups. Group one received 100mg clomiphene citrate (n=57) and group two received 5mg letrozole (n=50) daily on days 3-7 of their menstrual cycle. Human chorionic gonadotrplin (hCG) at a dose of 10000IU was administered when at least one mature follicle was observed. A single IUI was performed 34 hours later. Then size and number of mature follicles, ovulation rate, endometrial thickness and pregnancy rate was measured. FINDINGS: The number and the size of mature follicles were similar between two groups. The pregnancy rate in letrozole was 6% higher than clomiphene group (20% vs. 14%) that did not show significant difference. Endometrial thickness in letrozole and clomiphene citrate group was 64% and 64.9%, respectively. 86% of patients developed mature follicle in letrozole group who all of them showed ovulation, but in 72% of patients in clomiphene citrate group was developed mature follicles. CONCLUSION: Letrozole may be an acceptable alternative to clomiphene citrate for ovulation induction and pregnancy rate in PCOs patients