Clomiphene is a selective estrogen receptor modulator that impairs the activation of estrogen receptors (ERs) by 17β-estradiol. It potently binds both ERα and ERβ (Ki = 0.9 and 1.2 nM, respectively). Clomiphene enhances the release of gonadotropin-releasing hormone, stimulating the release of follicle-stimulating hormone and luteinizing hormone, culminating in ovulation.