ETHISTERONE

Fetal Risk Summary

The FDA mandated deletion of pregnancy-related indications for all progestins because of a possible association with congenital anomalies. No reports linking the use of ethisterone alone with congenital defects have been located. The Collaborative Perinatal Project monitored 866 mother-child pairs with 1st trimester exposure to progestational agents (including 2 with exposure to ethisterone) (1, pp. 389, 391). An increase in the expected frequency of cardiovascular defects and hypospadias was observed for the progestational agents as a group, but not for ethisterone as a single agent (1, p. 394). In a subsequent report from the Collaborative Study, a single case of tricuspid atresia and ventricular septal defect was identified with 3rd trimester exposure to ethisterone and ethinyl estradiol (2). Reevaluation of these data in terms of timing of exposure, vaginal bleeding in early pregnancy, and previous maternal obstetric history, however, failed to support an association between female sex hormones and cardiac malformations (3). An earlier study also failed to find any relationship with nongenital malformations (4). (See also Hydroxyprogesterone and Medroxyprogesterone)

Breast Feeding Summary

See Oral Contraceptives.

References

1. Heinonen OP, Slone D, Shapiro S. Birth Defects and Drugs in Pregnancy. Littleton, MA:Publishing Sciences Group, 1977.
2. Heinonen OP, Slone D, Monson RR, Hook EB, Shapiro S. Cardiovascular birth defects and antenatal exposure to female sex hormones. N Engl J Med 1977;296:67–70.
3. Wiseman RA, Dodds-Smith IC. Cardiovascular birth defects and antenatal exposure to female sex hormones: a reevaluation of some base data. Teratology 1984;30:359–70.
4. Wilson JG, Brent RL. Are female sex hormones teratogenic? Am J Obstet Gynecol 1981;141:567–80.