Venous thromboembolism in pregnant women with sickle cell disease: a retrospective database analysis.

Introduction: The risk of venous thromboembolism (VTE) is higher during pregnancy, with an incidence between 0.05 and 0.2%, and among persons with sickle cell disease (SCD), yet the rates and risk factors, such as pneumonia, vasooclusive crisis (VOC), and acute chest syndrome (ACS), associated with pregnancy-related VTE are not firmly established in SCD.

Methods: Inpatient hospital discharge data from 2007-2011 were obtained from the Pennsylvania Health Care Cost Containment Council to estimate the rate of VTE among African American delivery hospitalizations with SCD and to compare pregnancy complications and medical comorbidities among pregnant women with SCD.

Results: Among 212 hospitalized deliveries in African-American women with SCD, 6 (2.8%, 95% CI 1.0%-5.9%) had VTE compared to 0.05 to 2.0% in the general population. Risk factors for VTE included pneumonia and diabetes mellitus. Overall, the prevalence of VTE, among hospitalized deliveries in SCD women with pneumonia, VOC, and/or ACS, 6.6%, was significantly greater than among those without these conditions, 2.2%, p<0.001.

Conclusion: Pregnancy-related VTE in women with SCD appears to be 1.5 to 5 times greater than pregnancy-related VTE in the general population. The higher prevalence of VTE among pregnant women with pneumonia, VOC, and/or ACS, and their potential clinical overlap, suggests that VTE may be missed in such women. We conclude that VTE in pregnant women with SCD may be more common than previously reported, and such women might be candidates for thromboprophylaxis.