Abstract: Obstetrician-gynecologists are uniquely positioned to identify patients at risk of venous thromboembolism, a leading cause of morbidity and mortality in women. Pregnancy, use of exogenous estrogen, and gynecologic surgery represent three of the most provocative stimuli for venous thromboembolism; therefore, obstetrician-gynecologists should be aware of these and other risk factors, so that preventive measures can be implemented. Furthermore, because venous thromboembolism is increasingly common in these three clinical settings, it is important that obstetrician-gynecologists be fully versed in the diagnosis and treatment of venous thromboembolism.
This monograph describes the basic elements of the coagulation system, risk factors, and diagnostic algorithms for venous thromboembolism as well as various therapeutic agents available to treat venous thromboembolism. Strategies for screening patients who require gynecologic surgery, are planning pregnancy, are currently pregnant, or are using estrogen-containing hormone therapy (HT) also are described.
Venous thromboembolism is a leading cause of death in women (1). Its two prin-cipal presentations are 1) deep vein thrombosis (DVT), usually in leg veins, and 2) acute pulmonary embolism (PE). Approximately 90% of cases of the acute PE arise from DVT, particularly when proximal leg veins are the sites of the initial thrombus. The overall annual incidence of venous thromboembolism in the United States has been estimated to be 1.45 per 1,000 individuals, with DVT occurring in 4.8 per 10,000 individuals and acute PE in 2.3 per 10,000 individuals (1). The prevalence of both conditions increases markedly with increasing age. Patients with DVT also are at risk of chronic postphlebitic syndrome, characterized by venous ulceration, pain, and edema. Furthermore, based on claims data, the prevalence of venous thromboembolism is estimated to increase from 0.95 million in 2006 to 1.82 million in 2050 in the United States (2). This increase primarily reflects the aging of the population. Given the substantial mortality and morbidity associated with venous thromboembolism in women and the pathologic contributions of pregnancy, use of exogenous estrogen, and gynecologic surgery, it is important that obstetrician-gynecologists take the lead in identifying patients at risk, implementing preventive measures, promptly diagnosing thrombotic events, and ensuring that therapy is expeditiously initiated.