Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physician Assistant Studies (MPAS)


Physician Assistant Studies

First Advisor

Jay Metzger


infertility treatment; PCOS; letrozole; clomiphene citrate; safety; femara; clomid


Polycystic Ovarian Syndrome (PCOS) is the leading cause of anovulatory infertility and the most common endocrinopathy in women of reproductive age (Rosenfield & Ehrmann, 2016). It has been recognized that women with PCOS often struggle with infertility and require medication to stimulate ovulation to become pregnant. Currently, the first-line treatment for infertility associated with PCOS is clomiphene citrate, which was introduced in the 1960s (Morad & Farag, 2015). However, it has been proposed that an aromatase inhibitor, specifically letrozole, should become the first-line treatment for these patients due to a decreased adverse effect profile, a lower incidence of simultaneous multiple gestation pregnancies, and a decreased risk of congenital abnormalities. The purpose of this study is to determine if letrozole is an equal or better alternative to clomiphene citrate for infertility treatment in PCOS patients. An extensive literature review was performed, and letrozole was found to have higher ovulation rates, fewer twin pregnancies/more single births, higher pregnancy rates, and higher live birth rates compared to clomiphene citrate. There were conflicting results for endometrial thickness and single follicle stimulation. Neither letrozole or clomiphene citrate was superior to the other for ovarian hyperstimulation syndrome. There were no significant differences between letrozole and clomiphene citrate regarding congenital abnormalities and miscarriage rates. The results regarding ectopic pregnancies were comparable between both groups. In conclusion, the results provide information supporting letrozole as an adequate first-line alternative to clomiphene citrate for infertility in patients with PCOS.