[Does oral contraception cause cancer? (author's transl)].

A complete answer to the question of the relationship between malignant tumors in man and the administration of contraceptive steroids is at present not possible. Difficulties of the investigation are caused by the multiplicity of compounds used for contraception, the generally slow development of malignant tumors and the difficulty of the epidemiologic and statistical investigations on the multi-factorial etiology of cancer. Nevertheless, it can be stated with a high degree of certainty that "cancer due to the pill" does not exist in man and that a direct hormonal induction of malignant tumors in man cannot be proved. The question whether oral contraceptives may favor the development of cancer indirectly is explored in this paper regarding cancer of the female genital tract and the breast. No correlation between oral contraception and squamous cell carcinomas of the vulva and vagina and tumors of the ovary is known. As yet no statistics are available on the incidence of carcinoma of the endometrium in women who took oral contraceptives during their reproductive life span. Because of the direct hormonal suppression of the endometrial growth by oral contraception, a protective effect against endometrial hyperplasia and endometrial cancer must be expected. For cancer of the female breast no protective and no enhancing cancer risk due to progestational agents can be postulated. The known fragmentary data suggest a more protective value. Regarding dysplasia and carcinoma in situ of the uterine cervix large investigations in high numbers of patients are available. An increase of the risk to develop cancer of the cervix by using oral contraception cannot be shown with sufficient accuracy at our present state of knowledge by statistical means. Some observations suggest that oral contraception increases the relevant exogenous factors for carcinogenesis of the uterine cervix such as sexual behavior and hygiene.