Thrombosis in pregnancy and maternal outcomes

Abstract

Pregnancy increases the risk of thrombosis four- to five-fold. Seventy-five to eighty percent of pregnancy-related thrombotic events are venous and twenty to -twenty-five percent are arterial. The main reason for the increased risk is hypercoagulability. Women are hypercoagulable because they have evolved so that they are protected against the bleeding challenges of pregnancy, miscarriage, or childbirth. Both genetic and acquired risk factors can further increase the risk of thrombosis. The maternal consequences of thrombosis of pregnancy include permanent vascular damage, disability, and death. While the maternal outcomes of thrombosis can be modified by anticoagulation therapy, management of thrombosis during pregnancy is the subject of another paper in this issue (see paper by B. Konkle). This review will focus on the epidemiology, pathophysiology, risk factors, and maternal consequences of thrombosis in pregnancy.

Diagnosis and Management of Deep Vein Thrombosis and Pulmonary Embolism in Pregnancy

“…PAVTE consists of DVT (80%) and PE (20%). 14,17,18,30 These can occur antepartum (e.g., approximately two-thirds of pregnancy-associated DVT 18,31 ) or postpartum (e.g., up to 60% of pregnancy-associated PE 18 ). The highest risk of antepartum PAVTE is in the third trimester.…”

“…[42][43][44][45][46] The final component of Virchow's triad is hypercoagulability and this is thought to be the major factor influencing thrombosis in pregnancy. 30 Hypercoagulability in pregnancy is due to increases in prothrombotic coagulation factors accompanied by increased thrombin generation; decreases in naturally occurring anticoagulants; and reduced fibrinolysis. These changes are summarized in ►Table 2 and elaborated on later.…”

Pregnancy-associated adaptations in [Ca2+]i-dependent and Ca2+sensitization mechanisms of venous contraction: implications in pregnancy-related venous disorders

“…Importantly, the severity of pelvic congestion syndrome (7) and the risk of varicose veins (2,3,8,83,96), superficial and deep vein thrombosis, and venous thromboembolism increase during the course of pregnancy (9,39,50,66,92). In addition to blood hypercoagulability (33), changes in the vein wall mechanics and venous stasis (83) could play a role in pregnancy-related venous disorders. To understand the mechanisms involved in pregnancy-associated venous disorders, it is imperative to understand the cellular mechanisms regulating vascular function during normal pregnancy.…”

Accuracy of ultrasound to detect thrombosis in pregnancy: A systematic review

“…1 Pregnancy increases the risk of thrombosis three-to five-fold. 1,2 The venous system is more involved and can be identified in 75% of the cases. 2 Deep-vein thrombosis (DVT) is a life-threatening condition and is one of the main causes of death during pregnancy in developed countries.…”

“…1,2 The venous system is more involved and can be identified in 75% of the cases. 2 Deep-vein thrombosis (DVT) is a life-threatening condition and is one of the main causes of death during pregnancy in developed countries. 3 DVT is difficult to diagnose during pregnancy because its symptoms, including swelling of the legs, edema and pelvic or back pain, can be caused by physiologic changes.…”