The enzyme aromatase synthesizes estrogen, and aromatase inhibitor (AI) suppresses the production of estrogen.12 Ovarian stimulation with AI has been proposed as one of the treatments for infertility.13 AI blocks the aromatization of androgen to estrogen, and this has a similar effect to that of clomiphene citrate (CC), producing more follicles. The gene discussed is CYP19A1; the disease is Infertility.