1. Single 20 mg dose of Letrozole on day 3 of the menstrual cycle. Monitoring for response will include the usual measurements of serum Estradiol (E2), Follicle stimulating hormone (FSH), Luteinizing Hormone (LH), Progesterone (P) and transvaginal ultrasound for follicular count and endometrial thickness measurement. First monitoring will be on day 7 of the cycle and the rest of the monitoring will be determined according to response.