SHBG and endocrine system disorder: We selected a series of biological markers describing the clinical manifestation of PCOS, including sex hormone binding globulin (SHBG), testosterone levels, estrogen receptor (ER) and anti-Müllerian hormone (AMH) to evaluate endocrine disorder, infertility, anovulation, age at menarche and menopause to evaluate ovarian dysfunction, insulin-like growth factor-1 (IGF-1), homeostatic model assessment for insulin resistance (HOMA-IR), triglycerides and type 2 diabetes to evaluate insulin resistance.