Tahereh BehrouziLak, Masoomeh Hajshafiha, Rogiieh Derogar, Fedyeh Haghollahi
This study is a prospective randomized clinical trial that was conducted on 200 infertile patients with polycystic ovary syndrome (PCOS) in two groups (A and B). Group A (n=100) received Letrozole, 7.5 mg/day for 5 days (short-term group) from day 3 to 7 of menstruation. Group B (n=100) received Letrozole, 5 mg /day for 10 days (long-term group) from day 3 of menstruation. In both groups, the subcutaneous injections of human follicle stimulating hormone (Gonal-F) (75 IU) were applied on days of 5, 7, 9th menstrual cycles. When the follicle size was 18mm or more, human chorionic gonadotropin (hCG) (5000 IU) was injected intramuscular and after 34 to 36 hours, intrauterine insemination (IUI) was performed. The number of follicles and days to reach mature follicle, endometrial thickness, pregnancy and abortion were evaluated. The pregnancy and abortion rate were no differences in two groups. Endometrial thickness and number of mature follicles in group A (short-term) letrozole group are higher than the second group (p<0.05). The results of this small series suggest that short-term with totally low doses of letrozole offers benefit results, regarding number of mature follicles, endometrial thickness and could be the first line treatment for induction of ovulation in PCOS patients.