Coumarins administered in early pregnancy can cause malformations. This so-called coumarin embryopathy is characterized by malformations such as those occurring in chondrodysplasia punctata of the Conradi-Hünermann type, i.e. a syndrome which has been known since 1914. A case observed after coumarin administration (Falithrom) in early pregnancy is described with the features considered typical: Hypoplasia of the nasal bridge and stippled calcification of the skeleton, in particular stippled epiphyses of the long bones. According to reports in the literature, the risk of fetal abnormality amounts to some 30 per cent. This entails in practice the requirement for absolute contraindication for coumarins in early pregnancy (first trimester). Finally, possibilities of an acceptable anticoagulant therapy during pregnancy are discussed.