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Anticoagulation Therapy

Required most commonly for patients at high risk of thromboembolism (blockage of a blood vessel by a clot or thrombus formed elsewhere in the blood system and carried in the circulation). Venous thromboembolism (VTE) remains one of the main direct causes of maternal death. Better recognition of women at risk and more widespread use of thromboprophylaxis have led to a significant decline in such deaths. VTE can occur at any time during pregnancy but women are at highest risk during the puerperium. All women should undergo a documented assessment of risk factors for VTE in early pregnancy or prepregnancy. Women with four or more risk factors should be considered for prophylactic low molecular weight heparin (LMWH) throughout the antenatal period. Aspirin is not recommended for thromboprophylaxis in obstetric patients. In clinically suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) treatment with LMWH should be commenced immediately, unless treatment is strongly contraindicated. In pregnancy, early activation of the clotting system may contribute to later pathology of pre-eclampsia. As a result the use of anticoagulant or antiplatelet agents has been considered for the prevention of pre-eclampsia and fetal growth restriction. The World Health Organization recommends low dose aspirin (75 mg) only for women at high risk of developing the condition.


Royal College of Obstetricians & Gynaecologists (2015). Reducing the risk of venous thromboembolism during pregnancy and the puerperium. Green-top Guideline No 37a.

Royal College of Obstetricians & Gynaecologists (2015). Thromboembolic disease in pregnancy and the puerperium: acute management. Green-top Guideline No 37b

European Society of Cardiology (ESC) guidelines for the management of cardiovascular diseases during pregnancy. How to manage anticoagulation in pregnant women.

World Health Organization (WHO) (2011). WHO recommendations for prevention and treatment of pre-eclampsia and eclampsia.

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