Comparison of the Effect of Clomiphene- Estradiol Valerate vs Letrozole on Endometrial Thickness, Abortion and Pregnancy Rate in Infertile Women with Polycystic Ovarian Syndrome

Introduction Clomiphene citrate is the first-line therapy for ovulation induction in Polycystic Ovarian Syndrome (PCOS). This drug binds and blocks estrogen receptors and thought to have an anti estrogenic effect on endometrium volume, thus may have adverse effect on fertility.