Cyproterone paired with ethinyl estradiol is used in oral contraceptives that also treat the symptoms of hyperandrogenism in women (such as hirsutism and acne). Cyproterone acts as an antiandrogen (hence it's usefulness in treating acne and other effects of excess androgen) as well as a weak progestin and brings with it an increased risk of blood clots. Combined with estrogen, with also carries a risk of blood clots, this drug offers an even higher risk of the user developing blood clots.