In women with polycystic ovary syndrome (PCOS), the major abnormality is excessive ovarian androgen production marked by increased serum testosterone (T) and androstenedione (A) levels. Studies to determine the alteration in ovarian steroidogenesis that lead to abnormal production of ovarian androgens have revealed increased CYP17 gene expression with accentuated 17-hydroxylase activity leading to exaggerated 17-hydroxyprogesterone (17P) responses to LH stimulation. In contrast, T and A responses did not distinguish between PCOS and normal women, although these androgens were clearly greater in the former compared to the latter group. As a result, 17P responsiveness has been employed to determine the functional capacity of the ovary to produce androgen. Stimulatory agents have included GnRH agonist, Lupron, at a dose of 10 microgram per kilogram, or hCG at a dose of 10,000 IU.