Minor Transplacental Passage of Fondaparinux in Vivo

Abstract
Low-molecular-weight heparin remains the anticoagulant of choice for pregnant women with previous thromboembolic events. Fondaparinux (Arixtra, Sanofi-Synthelabo) is a chemically synthesized derivative of the natural pentasaccharide sequence that mediates the interaction of heparin with antithrombin.1 It has been recommended for prophylaxis against thromboembolism after hip or knee surgery.2,3