IGFBP1 and polycystic ovary syndrome: Moreover, previous data demonstrated that, compared to normo-ovulatory women, PCOS patients might exhibit a dysregulation in the IGF system represented as an elevation in the serum levels of free insulin-like growth factor-1 (IGF-1) and a reduction in the serum levels of insulin-like growth factor binding protein-1 (IGFBP-1) [4].