Multiple congenital anomalies associated with oral anticoagulants

Abstract

The administration of oral anticoagulants during the latter part of pregnancy is known to cause fetal or placental hemorrhage. In addition, there is increasing evidence that the administration of oral vitamin K antagonists or warfarin-related compounds during the first 8 weeks of gestation may result in congenital malformations. The most consistent malformations include nasal hypoplasia, stippling of bones, ophthalmologic abnormalities, intrauterine growth retardation, and developmental delay. Whether the malformations are a result of microhemorrhages in embryonic cartilage, the result of an unknown, more widespread teratogenic effect, or a manifestation of fetal vitamin K deficiency remains to be clarified. Women for whom anticoagulation during pregnancy is mandatory should probably be maintained on heparin during the first 12 weeks of gestation. If oral anticoagulants are necessary or have been given during the first trimester, the mothers should be warned about the possible congenital malformations. The administration of oral anticoagulants during the latter part of pregnancy is known to cause fetal or placental hemorrhage. In addition, there is increasing evidence that the administration of oral vitamin K antagonists or warfarin-related compounds during the first 8 weeks of gestation may result in congenital malformations. The most consistent malformations include nasal hypoplasia, stippling of bones, ophthalmologic abnormalities, intrauterine growth retardation, and developmental delay. Whether the malformations are a result of microhemorrhages in embryonic cartilage, the result of an unknown, more widespread teratogenic effect, or a manifestation of fetal vitamin K deficiency remains to be clarified. Women for whom anticoagulation during pregnancy is mandatory should probably be maintained on heparin during the first 12 weeks of gestation. If oral anticoagulants are necessary or have been given during the first trimester, the mothers should be warned about the possible congenital malformations.