Biochemically, hyperandrogenism is usually assessed by assay of total testosterone (TT), free testosterone (fT), sex hormone binding globulin (SHBG), androstenedione (A), 17-hydroxy progesterone (17-OHP) and dehydroepiandrosterone sulphate (DHEAS) in serum and by calculation of the free androgen index (FAI = (TT/SHBG)100). This evidence concerns the gene SHBG and hyperandrogenism.