Furthermore, IR and associated hyperinsulinemia are related to abnormal ovarian steroidogenesis [59] and can concur to the pathogenesis of anovulation and hyperandrogenism [60, 61]; in particular, hyperinsulinemia stimulates theca cell proliferation, amplifies LH-mediated androgen secretion, and increases expression of LH and insulin growth factor-1 (IGF-1) receptor. This evidence concerns the gene PLOD1 and anovulation.