Warfarin is a coumarin derivative used as an anticoagulant in the prophylaxis and treatment of various thromboses and thromboembolic disorders. Mechanistically, it interferes with the hepatic synthesis of a number of vitamin-K-dependent coagulation factors. In fact, an association between deficiency of these factors and the malformative phenotype induced by warfarin has been made. In humans, warfarin is associated with several different phenotypes induced by it. It is established that there are two distinct types of defects associated with the coumarin drugs, especially warfarin, dependent on the time administered during pregnancy. Warfarin given during pregnancy in humans induces all classes of developmental toxicity, whether given early or late in gestation. Warfarin is an average-sized hydrophobic human developmental toxicant. It is of average polarity in comparison to the other compounds. Warfarin can engage in hydrogen bonding interactions, primarily as a hydrogen bond acceptor.