Pulmonary embolism in pregnancy. Consensus and controversies

Venous thrombotic events (VTE) occur 1-2 per 10,000 pregnancies and remain one of the leading causes of maternal mortality in the developed world. The two largest risk factors are a personal history of VTE and heritable thrombophilias. D-dimer tests for VTE in pregnancy have a high false positive rate and at least some false negatives have been reported. Compression ultrasound should be used to evaluate pregnant women for deep venous thrombosis followed by magnetic resonance imaging of the pelvis for a negative test and strong remaining clinical suspicion. For pulmonary embolism, a chest x-ray should be used to triage the patient to either a ventilation/perfusion study after a normal X-ray or a CT pulmonary angiogram after an abnormal one. Treatment generally consists of low molecular weight heparin through a minimum of six weeks post-partum. Thombolysis might have merit in life-threatening, massive pulmonary embolism. VTE prophylaxis in at-risk populations remains a major area of uncertainty. Mechanical prophylaxis for all women undergoing cesarean, in particular, has a paucity of supportive evidence.