The invention relates to 17-hydroxy-17-pentafluoroethyl-estra-4,9(10)-dien-11-aryl derivatives of Formula I with progesterone antagonizing action and method of production thereof, use thereof for the treatment and/or prophylaxis of diseases and use thereof for the production of medicinal products for the treatment and/or prophylaxis of diseases, in particular of fibroids of the uterus (myomas, uterine leiomyoma), endometriosis, heavy menstrual bleeds, meningiomas, hormone-dependent breast cancers and complaints associated with the menopause or for fertility control and emergency contraception.