[Teratology "from Geoffroy Saint-Hilaire to the present"].

Teratology, science of monsters, exists during the periods of Antiquity, Middle Ages, Renaissance, ... but its comes more precise at the XIXth century with Etienne. Geoffroy Saint Hilaire who studies several anomalies; he was interested in celosomia, cyclocephalia, anencephaly, twin monsters ... His son, Isidore Geoffroy Saint Hilaire, creates the word "Teratologie" and specifies the teratologic classification; he studies omphalosites, celosomia, hermaphrodite, twin monsters. During the XIXth century, the development of experimental embriology and teratogenesis is very important. During le XXth century the studies of morphologic teratology are specified. Famous living monsters are described; experimental teratogenese is improved; the mecanism and the etiology are more known. It is also the beguining of the teratologic surgery and of the antenatal diagnostic.