Letrozole as the first-line treatment of infertile women with poly cystic ovarian syndrome (PCOS) compared with clomiphene citrate: A clinical trial


Department of Gynecology and Obstetrics, Isfahan University of Medical Sciences, Isfahan, Iran


Background: The purpose of this study was to determine the efficacy and safety of letrozole on ovulation induction and pregnancy in comparison with clomiphene citrate in PCOS patients.
Materials and Methods: The study was based on prospective randomized clinical trial comparing the efficacy of letrozole as the first-line management of the PCOS patients in comparison to clomiphene citrate during 2009 to 2011 and was performed in one private infertility clinic. The study included 100 patients divided into 2 equal groups.
Results: Pregnancy occurred in 29 of 50 patients in letrozole group (58%) and 24 of 51 patients in clomiphene group (47%). The difference was not statistically significant (P value = 0.23). Thirty patients in clomiphene group and 36 patients in letrozole group showed regular menses after or during the treatment course. No significant difference between the 2 groups was observed (P value = 0.21).
Conclusion: Our findings suggest letrozole and clomiphene citrate are equally effective for induction of ovulation and achieving pregnancy in patients with PCOS.


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