[Teratogenic effects of etretinate in humans]

Etretinate (Tigason) is an orally administered retinoid which is used primarily for the treatment of severe keratinization disorders of the skin. The compound has been shown by animal studies to be teratogenic. Because of its lengthy period of storage in the body, the teratogenic risk in humans persisting even after cessation of therapy is an important problem. Despite insistent warnings, female patients have become pregnant in temporal relationship to etretinate therapy. According to observations reported to the manufacturers until February 1984, 19 women had taken etretinate during pregnancy; ten of these patients bore children with no recognizable teratogenic abnormalities. Three women bore children with skeletal defects which had to be attributed to etretinate. One woman had a spontaneous abortion in the 5th month; the fetus was found to have a meningomyelocele. Two fetuses which were aborted for medical reasons had marked cerebral abnormalities. A further 3 fetuses from interrupted pregnancies showed no defects. Among 18 women who became pregnant within two years after etretinate having been discontinued there was no case of teratogenic damage to the embryo. Even if, to date, no malformed infants have been born to woman conceiving after stopping etretinate therapy, the stipulated period of pregnancy prevention after withdrawal of etretinate must continue to be scrupulously respected, since etretinate is apparently teratogenic.