Introduction

Pregnancy is associated with physiologic and anatomic changes that increase the risk of thromboembolism. Pregnancy also alters the levels of coagulation factors normally responsible for hemostasis, so the overall effect of these changes is an increase in thrombogetic capability. The most important individual risk factor for VTE in pregnancy is a personal history of thrombosis. 15 to 25% of all cases of VTE during pregnancy are recurrent events.