Letrozole is as effective as clomiphene citrate for induction of ovulation in patients with PCOS. Adequate endometrial development is required for pregnancy to occur, and pregnancy rates were found to be higher when the endometrium reached at least 10 mm thickness. 

Letrozole is as effective as clomiphene citrate for induction of ovulation in patients with PCOS. Adequate endometrial development is required for pregnancy to occur, and pregnancy rates were found to be higher when the endometrium reached at least 10 mm thickness.