Research Article| Volume 6, ISSUE 2, P111-118, June 1996

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Anticoagulants in pregnancy

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      Anticoagulants may be indicated during pregnancy for the treatment or prophylaxis of venous thromboembolism and, in patients with mechanical prosthetic cardiac valves, for the prevention of valve thrombosis and systemic embolisation. Occasionally, anticoagulation is also indicated in pregnant women with valvular or congenital heart disease.
      Maternal mortality statistics highlight pulmonary embolism as a leading cause of maternal death in the Western world. These statistics, and the increasing understanding of risk factors for thrombosis, are leading to an increase in usage of anticoagulant drugs during pregnancy and the puerperium. Knowledge of the basic pharmacology, potential adverse effects, clinical indications and the special considerations relating to use of these agents during pregnancy is, therefore, important for obstetricians. Heparin is the anticoagulant of choice for prevention and treatment of venous thrombosis during pregnancy, as it does not cross the placenta. Warfarin should generally be avoided in pregnant women because it crosses the placenta and may give rise to fetal abnormalities. On the other hand, as the efficacy of heparin in the prevention of systemic embolisation from prosthetic cardiac valves is still unproven, warfarin remains the anticoagulant of choice in the middle of pregnancy for such patients.
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