INS and Hirsutism: Additionally, it can limit the formation of hepatic SHBG (sex hormone-binding globulin) and increase free testosterone levels.8 Hirsutism in PCOS is caused by excess androgen production from the ovaries and increased sensitivity of the pilosebaceous unit to androgens and insulin.9 Additionally, according to Itami et al., androgen stimulates the growth of hair follicles in association with insulin and insulin-like growth factors.10