Venous thromboembolism during pregnancy and the postpartum period: incidence, risk factors, and mortality.

OBJECTIVE: The purpose of this study was to estimate the incidence, risk factors, and mortality from pregnancy-related venous thromboembolism.

STUDY DESIGN: The Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality for the years 2000 to 2001 was queried for all pregnancy-related discharges with a diagnosis of venous thromboembolism.

RESULTS: The rate of venous thromboembolism was 1.72 per 1000 deliveries with 1.1 deaths per 100,000. The risk of venous thromboembolism was 38% higher for women ages 35 and older and 64% higher for black women. Other significant risk factors included thrombophilia, lupus, heart disease, sickle cell disease, obesity, fluid and electrolyte imbalance, postpartum infection, and transfusion. The risk factor with the highest odds ratio, 51.8 (38.7-69.2) was thrombophilia.

CONCLUSION: The incidence of pregnancy-related venous thromboembolism was higher than generally quoted. Women ages 35 and older, black women, and women with certain medical conditions and obstetric complications appear to be at increased risk.