Pregnancy-Induced Hypertension, But Not Gestational Diabetes Mellitus, Is a Risk Factor for Venous Thromboembolism in Pregnancy

Background and Objectives: The aim of this study was to identify the association of pregnancy-induced hypertension (PIH) or gestational diabetes mellitus (GDM) with the development of venous thromboembolism (VTE). Subjects and Methods: This was a retrospective study of 57,009 pregnancies during 2002-2008 at Cheil General Hospital, Kwandong University. The diagnosis of VTE {deep vein thrombosis or pulmonary embolism (PE)} was based on clot visualization via ultrasound or computed tomography. Results: In total, 27 cases (PE, 20 cases) were detected. The incidence of VTE was 0.47 per 1,000 pregnancies. To determine risk factors associated with pregnancy-induced VTE, univariate analysis using a chi-square test was performed. Cesarean (C)-section, multiple pregnancy, PIH, placenta previa, and assisted reproduction technique (ART) were statistically significant compared to the controls (all, p=0.000). However, age, premature rupture of membrane, and GDM were not statistically related to VTE. Logistic regression analysis was used to calculate the odds ratios for the risk factors. Placenta previa showed a 12.6-fold higher risk, while PIH had a 9.8-fold higher risk for the occurrence of VTE. C-section and ART procedures increased the risk of VTE by 4.2 times compared to that of the controls. Conclusion: Placenta previa and PIH were significant risk factors for VTE, whereas the known traditional risk factors of increased age and GDM were not found to be associated with VTE.