International Agency for Research on Cancer (IARC) - Summaries & Evaluations


VOL.: 21 (1979) (p. 387)

5. Summary of Data Reported and Evaluation

(N.B. - This section should be read in conjunction with the General Remarks on Sex Hormones and with the General Conclusions on Sex Hormones.)

5.1 Experimental data

Ethynodiol diacetate was tested in mice, rats and monkeys alone or in combination with oestrogens by oral administration. In castrated male mice, it increased the incidence of mammary tumours, and in male rats it produced benign mammary tumours. In combination with oestrogens, it increased the incidence of pituitary tumours in mice and of malignant mammary tumours in male and female rats. The study in monkeys is still in progress.

Ethynodiol diacetate was reported to be embryolethal for pre- and postimplantation embryos and to have teratogenic effects in some species.

5.2 Human data

No case reports or epidemiological studies on ethynodiol diacetate alone were available to the Working Group. Epidemiological studies on steroid hormones used in oestrogen-progestin oral contraceptive preparations have been summarized in the section, 'Oestrogens and Progestins in Relation to Human Cancer'.

5.3 Evaluation

There is limited evidence for the carcinogenicity of ethynodiol diacetate in animals. In humans, oral contraceptives containing oestrogens in combination with progestins have been related causally to an increased incidence of benign liver adenomas and a decreased incidence of benign breast disease.

For definition of the italicized terms, see Preamble Evaluation.

Previous evaluation: Vol. 6 (1974)

Subsequent evaluation: Suppl. 7 (1987) (Progestins; combined oral contraceptives)

Last updated: 7 April 1998

    See Also:
       Toxicological Abbreviations
       Ethynodiol Diacetate (IARC Summary & Evaluation, Volume 6, 1974)