INS and polycystic ovary syndrome: For the improvement of hyperandrogenemia, metformin can reduce androgen secretion from thecal cells and adrenal glands of women with PCOS while stimulating SHBG production, modulating LH discharge, and attenuating the ovarian androgen response to gonadotropin stimulation by reducing circulating insulin and androgen levels, thus reducing FT concentration (39, 40).