Comparing the effect of clomiphene citrate and letrozole on ovulation induction in infertile women with polycystic ovary syndrome

To compare the effects of letrozole and clomiphene citrate in women with polycystic ovaries. The double-blind randomised clinical trial study was conducted from September 22, 2012 to March 20, 2013, at the Islamic Azad University of Medical Sciences, Mashad, Iran, and comprised infertile women with polycystic ovaries. The subjects were classified into two groups. Patients who received letrozole 5mg tablets per night formed group A, and those who received clomiphene citrate 50mg tablets per night formed group B. The medication continued for 3-7 days in each group. On the 13th day, transvaginal sonography with multi-frequency vaginal probe was done to check the number and the size of dominant follicle and endometrial thickness. Human chorionic gonadotrophin 5000 IU ampoule, 10000 IU per night, was administered intramuscularly for ovulation in the case of dominant follicle over 18mm and the insemination was recommended 24-36h after injection. Beta human chorionic gonadotrophin was determined 16 days after the injection by immunoassay technique. The patients were followed up for 12 months. SPSS 16 was used for data analysis. There were 220 patients; 110(50%) in each of the two groups. The mean age of patients in group A was 26.2±3.6 years and that in group B was 27±3.6 years. Endometrial thickness in group A was significantly greater compared to group B (p=0.001). The clinical consequence of drug use (pregnancy) in group A was better than group B (p=0.007). Although more clinical studies are needed, letrozole is recommended for women with polycystic ovaries and those resistant to clomiphene citrate.