Congenital malformation registries were established in many industrialized countries following the thalidomide tragedy, which resulted in the birth of thousands of children with severe birth defects between 1956 and 1961. France currently has four birth defect registries: the Paris Registry, the Alsace Registry, the Rhône-Alpes Birth Defect Registry (Remera), and the Center for the Study of Congenital Malformations in Auvergne (CEMC-Auvergne). These registries provide systematic epidemiological surveillance of pregnancy outcomes in 14 departments, accounting for approximately 16% of French births. They are part of international networks of birth defect registries. At the initiative of the French Institute for Public Health Surveillance (InVS), they are currently working to harmonize their practices with a view to forming a national network. The primary role of these population registries is the early detection of clusters of birth defects resulting from the introduction of a new teratogenic agent into the environment. For example, data from the former Centre-Est registry enabled the detection of the teratogenic effect of sodium valproate on spina bifida. With the development of preventive measures, this surveillance and early warning mission has gradually been supplemented by a key role in evaluating, at the population level, the impact of public health policies in the field of perinatal care. (R.A.)