The HPO axis is altered in PCOS in that GnRH (gonadotropin-releasing hormone) pulsatile secretion rates are increased, leading to higher LH relative to FSH (follicle stimulating hormone), higher AMH (antimüllerian hormone) and lower SHBG (serum hormone binding globulin) in conjunction with higher postnatal serum testosterone and lower oxytocin [3]. This evidence concerns the gene PLOD1 and polycystic ovary syndrome.