P-62: Extended Letrozole Therapy for Ovulation Induction in Women with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in young women which has different clinical consequences. This study was conducted to evaluate the outcome of long or extended letrozole therapy for induction of ovulation in patients with polycystic ovary syndrome (PCOS). Materials and Methods: This prospective controlled study was conducted in a university hospital on 107 patients with PCOS. Patients were randomly allocated to treatment with either long letrozole therapy or short letrozole therapy. The diagnosis of PCOS was based on Rotterdom diagnostic criteria. Patients in the short letrozole group had 5 mg of letrozole daily starting day 1 of the menses for 5 days and patients in the long letrozole group had 2.5 mg of letrozole daily starting day 1 of the menses for 10 days. Number of growing and mature follicles, endometrial thickness, occurrence of pregnancy and miscarriage were evaluated. Results: There was 46 PCOS patients in long letrozole therapy group and 61 PCOS patient in short letrozole therapy group. Number of growing and mature follicles, endometrial thickness, and occurrence of pregnancy were interestingly noticeable in the first group. Although the pregnancy rate was not significantly different in both groups, but considering both methods in clinical practice is recommended. Conclusion: The long letrozole protocol (10 days) can produce mature follicles and pregnancies similar to the short letrozole thrapy (5 days).