Figure 6. Mechanisms of adrenal hyperandrogenism. Elevations in adrenocorticotropic hormone, increases in neural-adrenomedullary input, and presence of insulin-mediated metabolic input may lead to adrenal hyperandrogenism and premature adrenarche. In turn, adrenal hyperandrogenism, insulin resistance, or both may lead to full-blown polycystic ovary syndrome in a woman with an inherent ovarian vulnerability. ACTH = adrenocorticotropic hormone; CRH = corticotropin-releasing hormone; E = epinephrine; NE = norepinephrine; NPY = neuropeptide Y.