Venous thromboembolism is a major cause of maternal morbidity and mortality, and accurate diagnostic workup upon suspicion of deep vein thrombosis or pulmonary embolism in a pregnant woman is of utmost importance. The diagnostic repertoire for venous thromboembolism is, however, less well studied in pregnant women. The clinical assessment is influenced by common symptoms of pregnancy such as leg swelling or shortness of breath. The role of D-Dimer is limited, since - even during uncomplicated pregnancy - D-Dimer levels increase with gestational age. Preliminary data indicate that a normal D-Dimer in a healthy pregnant woman with a low clinical probability may exclude deep vein thrombosis. Compression ultrasonography and ventilation perfusion scanning or helical computed tomography are the imaging techniques of choice in a pregnant woman with suspected deep vein thrombosis or pulmonary embolism, respectively. The role of magnetic resonance imaging for the diagnosis of venous thromboembolism during pregnancy is uncertain and contraindications particularly to contrast media have to be considered.