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Pulmonary embolism in pregnancy: Epidemiology, pathogenesis, and diagnosis

David R Schwartz, MD
Atul Malhotra, MD
Steven E Weinberger, MD
Section Editors
Lawrence LK Leung, MD
Jess Mandel, MD
Charles J Lockwood, MD, MHCM
Deputy Editor
Geraldine Finlay, MD


Pregnancy and the puerperium (postpartum period) are well-established risk factors for venous thromboembolism (VTE), with VTE occurring in approximately 1 in 1600 pregnancies [1-3].

VTE can manifest during pregnancy as an isolated lower extremity deep venous thrombosis (DVT) or clot can break off from the lower extremities and travel to the lung to present as pulmonary embolus (PE). In the United States, PE is the sixth leading cause of maternal mortality [4-7]. Preventing deaths from PE in pregnancy requires a high index of clinical suspicion focused on an accurate diagnostic approach so that appropriate treatment with anticoagulation can be initiated in a timely fashion.

The diagnosis of PE during pregnancy will be reviewed here. The epidemiology and pathogenesis of VTE, the diagnosis of DVT during pregnancy, and the prevention and treatment of DVT and PE during pregnancy are discussed separately. (See "Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis" and "Deep vein thrombosis and pulmonary embolism in pregnancy: Prevention" and "Deep vein thrombosis and pulmonary embolism in pregnancy: Treatment".)


The epidemiology of VTE during pregnancy and the puerperium is discussed separately. (See "Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis", section on 'Epidemiology'.)


Factors that increase the risk of VTE during pregnancy and the puerperium are discussed separately. (See "Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis", section on 'Compressive ultrasound and subsequent testing'.)

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Literature review current through: Nov 2017. | This topic last updated: Feb 15, 2017.
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