The majority of deep vein thrombosis (DVT) in pregnancy is iliofemoral with a greater risk of both embolisation and recurrence. A thrombus may detach from its site of origin in the vein and migrate through the blood stream to reach the lungs (pulmonary embolism (PE)). The rationale for prophylaxis is based on its efficacy, the clinically silent nature of venous thromboembolism (VTE), its prevalence in pregnant or puerperal patients and its potentially disabling or fatal consequences. Compression duplex ultrasound is the preferred initial imaging test in pregnancy as this test has a high sensitivity and specificity when compared with contrast venography. Treatment of acute-phase VTE is done by administering low-molecular-weight heparin (LMWH) either given once daily or in two divided doses subcutaneously with dosage calculated according to the woman's recent weight. The use of thrombolytic therapy during pregnancy should be reserved for women with severe pulmonary thromboembolism with haemodynamic compromise.