This is likely due to not well-controlled serum insulin concentrations in obese women with PCOS despite continuing metformin, which may eventually result in increased stimulation of androgen production from the ovaries, increase in the sensitivity of the pituitary gland to the effects of gonadotrophin-releasing hormone, and increase in steroid production from the adipose tissues21,25,26,29,30. This evidence concerns the gene INS and polycystic ovary syndrome.