This, in addition to hyperandrogenism in most women with PCOS, disrupted hypothalamo-pituitary function leading to increased LH pulse frequency, increased LH/FSH ratio and a persistently rapid frequency of gonadotropin-releasing hormone (GnRH) pulse secretion, suggests an impaired feedback mechanism between gonads and the brain (46). This evidence concerns the gene GNRH1 and hyperandrogenism.