Chlormadinon acetate is a synthetic sex hormone (progestin) and therefore has a steroid scaffold. It acts antiestrogen, this disrupts egg transport and sperm penetration into the uterus. At higher doses, the release of gonadotropic hormones can be inhibited. It partial displaces androgens from their receptors (antiandrogen) and therefore can treat androgen-dependent diseases such as uterine mucous membrane cysts or acne seborrhoica. The main uses are hormonal contraception, but also hormonal disorders in women.