The Induction of Ovulation in Women with Polycystic Ovarian Syndrome Via: Letrozole vs Clomiphene Citrate

Background and objectives: Anovulatory infertility 75%-caused by polycystic ovary syndrome (PCOS), a worldwide-occurred fertility disorder. The current investigation was conducted to compare the ovulation-induction effect of letrozole (LZ) to that from clomiphene (CP) and study the endometrial thickness (ET), endometrial blood flow (EBF), and pregnancy rate (PR) after using these compounds. Patients and Methods: this study was a comparative study that was performed in the outpatients consultation unit in the Department of Obstetrics and Gynecology in Al-Diwaniyah Maternity and Pediatrics Teaching Hospital, Iraq, from the period of January 2018-May 2019. Atotal of 100 patients were enrolled in the study aged 20-40 years, with anovulation infertility due to polycystic ovary syndrome,with BMI 19-30 kg/m(2) who were desiring to conceive and require fertility medication and the participant patients randomly divided into two groups: Group 1 :include 50 women assigned to have LZ tab 2.5 mg/twice daily starting from day 2 for 5 days. Group 2: include 50 women assigned to have CP 50 mg/twice daily starting from day 2 of the cycle for 5 days and repeated ultrasonography was performed and follicular size, ovulatory rate, ET, endometrial or sub-endometrial spiral artery vascularity (pulsitility index PI) and resistant index (RI) Doppler and PR were determined. Results: Age (28.61 +/- 4.66 years) and body mass index (BMI) were found with no significant (p>0.05) differences between LZ group and CP group. ET in LZ group (6.78 +/- 0.86mm) was significantly (p<0.05) higher than that of CP group (4.94 +/- 0.59mm). There was no significant difference in mean number of follicles between study groups (p = 0.735). Mean resistive index (RI) was significantly lower in LZ group in comparison with CP group, 0.54 +/- 0.06 versus 0.65 +/- 0.06, respectively (p < 0.001). Mean pulsatility (PI) index was significant lower in LZ group in comparison with CP group, 1.14 +/- 0.10 versus 1.39 +/- 0.10, respectively (p < 0.001). Positive biochemical pregnancy in LZ was 14.0% and in CP group was 10.0 %; however, there was no significant difference in pregnancy outcome between both groups (p = 0.538). Conclusion: the effect of LZ for ovulation induction in anovulatory PCOS women showed a significantly better endometrial response and receptivity that may increase fertility when compared with CP