Warfarin-associated embryopathy in a 17-week-old abortus.

Histological and anthropometric studies were made of the hands and face of a 17-week-old (postmenstrual) human fetus that was exposed to warfarin throughout gestation. The fetus had marked nasal hypoplasia and the facial cartilages contained discrete foci of abnormal cartilage. When compared with age-matched control fetuses hand pattern profile analysis showed that the brachydactyly was due to shortening of the terminal phalanges. Histologically chondrogenesis was disordered in the carpals and phalanges, with the most deviant development occurring at the distal ends of the terminal phalanges. In none of the areas of abnormal cartilage was there evidence of hemorrhage or hemosiderin deposition. It is our contention that warfarin is teratogenic in human beings and that its teratogenicity is not due to focal hemorrhage.