What are the special considerations for anticoagulation during the pregnancy, birth and postpartum period?
Women with the Marfan syndrome who have had aortic surgery with aortic and/or mitral valve replacement prior to pregnancy or other indications for anticoagulant therapy require special consideration. In the United States, anticoagulation during pregnancy is usually accomplished with subcutaneous injections of heparin.-. Heparin is a large molecule, does not cross the placenta and has not been associated with birth defects. Most people who are on chronic anticoagulation receive Coumadin, a small molecule that interferes with the action of Vitamin K in the liver and reduces the efficiency of action of several clotting factors. Coumadin is taken orally and provides effective anticoagulation. Because it is a small molecule, Coumadin crosses the placenta and has been associated with birth defects called the fetal warfarin syndrome. This syndrome includes abnormalities of the eyes, nose, limbs and central nervous system, as well as loss of hearing. For this reason, Coumadin is not used durin
