Warfarin is an anticoagulant used in the prevention and treatment of thrombosis and thromboembolism. Warfarin passes through the placental barrier and may cause bleeding in the foetus, resulting in central nervous system damage.

Exposure to warfarin during early pregnancy from the sixth week onwards may cause cartilage and bone maldevelopment in the foetus.

If you are taking warfarin and planning a pregnancy, contact your physician without delay if you have missed your periods or your pregnancy test is positive. Warfarin will be replaced by heparin by the sixth week of pregnancy. On rare occasions, it may be necessary to start taking warfarin later in pregnancy.