Deep venous thrombosis and pulmonary embolism in obese women

• Obesity is a risk factor for venous thromboembolism in pregnancy and the puerperium.
• Guidelines on prophylaxis have reduced maternal mortality from thromboembolism.
• The dosages of heparin for both prophylaxis and treatment are weight related.
• More lives could be saved in the future by better adherence to guidelines.
• Research is needed on the links between pregnancy, obesity and thromboembolism.

Obesity increases the risk of venous thromboembolism, and pregnancy also increases the risk, particularly around delivery and in the puerperium. Pregnancy complications, which often involve bed rest in hospital, increase the risk still further. This chapter reviews recent studies aimed at quantifying these risks and discusses the mechanisms linking obesity, pregnancy and thromboembolism. It is now apparent that obesity is a proinflammatory condition that creates a prothrombotic milieu, but as yet little is known about how this interacts with pregnancy. Awareness of interacting risk factors has led to guidelines for risk assessment in pregnancy, and implementation of thromboprophylaxis guidelines has been followed by a dramatic fall in deaths from thromboembolism, which was for many years the leading cause of direct maternal deaths in the UK. This chapter summarises the guidelines on the prevention, diagnosis and treatment of thromboembolism in pregnancy and discusses the next steps to further reduce mortality.