Objective: To assess familial cardiovascular risk factors in women developing hypertension in pregnancy.
Method: Of 2211 women delivering live births after enrollment in a pregnancy cohort study, 85 (3.8%) developed preeclampsia (antepartum systolic blood pressure greater than 140 or diastolic blood pressure greater than 90 plus proteinuria) and 142 (6.4%) developed transient hypertension of pregnancy (antepartum blood pressure elevation without proteinuria). At a mean of 10.2 weeks' gestation, women were asked about first-degree family members with heart disease or stroke, hypertension, diabetes, renal disease, or any of these, which defined familial cardiovascular risk.
Results: After adjustment for age and body size, having two or more family members, versus no family members, with cardiovascular risk imparted a 1.9-fold (95% confidence interval [CI] 1.1, 3.2) elevated risk for developing preeclampsia and a 1.7-fold (95% CI 1.1, 2.6) risk for developing transient hypertension of pregnancy. Having two or more family members with hypertension also imparted a significant, two-fold elevation in risk of preeclampsia and transient hypertension of pregnancy, and having two or more family members with heart disease or stroke imparted a 3.2-fold (95% CI 1.4, 7.7) elevation in the risk for preeclampsia.
Conclusion: A strong family history of aggregate cardiovascular risk increased the likelihood for developing preeclampsia and transient hypertension of pregnancy. These findings support the theory that a preexisting tendency to cardiovascular risk, and particularly hypertension, increases a women's susceptibility to developing hypertension in pregnancy.