Women's Cardiovascular Health After a Hypertensive Disorder of Pregnancy

More than a quarter of parous women experience a complication during pregnancy, such as a hypertensive disorders of pregnancy (HDP) (preeclampsia or gestational hypertension), gestational diabetes, fetal growth restriction, or preterm delivery. Substantial evidence shows that these women are approximately twice as likely as those with uncomplicated pregnancies to later develop cardiovascular disease (CVD) (1). Using data from NHS II (Nurses' Health Study II), Stuart and colleagues report associations between a history of a first pregnancy complicated by an HDP and physician-diagnosed hypertension, hypercholesterolemia, and type 2 diabetes over the course of 3 decades after pregnancy (2). They found that women who had preeclampsia in their first pregnancy had a 2.2-fold increased risk for hypertension, a 75% increased risk for type 2 diabetes, and a 31% increased risk for hypercholesterolemia compared with those who were normotensive during their first pregnancy. The respective estimates for women who had gestational hypertension in their first pregnancy were 2.8-fold, 65%, and 36%. Analyses not restricted to first pregnancies yielded similar results. Stuart and colleagues accounted for a wide range of prepregnancy risk factors, including body mass index, that may confound the relationship between HDPs and CVD risk factors. However, they were unable to adjust for prepregnancy blood pressure, cholesterol level, or glucose level because of a lack of relevant data. Therefore, the nature of the association between HDPs (and other pregnancy complications) and CVD remains to be clarified. Do HDP per se contribute to the increased CVD risk, or do they simply identify women who have failed the cardiometabolic stress test of pregnancy because of a preexisting increased propensity for CVD? The nature of the relationship between pregnancy complications, such as HDP, and CVD has practical implications. If HDP increase CVD risk independently of prepregnancy cardiovascular health (for example, by causing end-organ damage), prevention of such complications has the potential to reduce the burden of CVD in women. If, on the other hand, prepregnancy cardiovascular health is key, prevention efforts should be aimed at young women before conception. To clarify the nature of the relationship between pregnancy complications and subsequent CVD, detailed measures of prepregnancy cardiovascular health, in addition to information on pregnancy complications and characterization of long-term maternal cardiovascular health after pregnancy, are needed. Yet, pregnancy and birth cohorts typically recruit women who are already pregnant and therefore do not include data on cardiovascular health before conception. Stuart and colleagues also found that women with a history of HDP developed CVD risk factors at an earlier age than those without HDP. This finding is both novel and important because it suggests that women with a history of HDP could benefit from cardiovascular risk assessment at an earlier age than those without HDPs. Recent U.S. and European clinical guidelines (35) include a woman's obstetric history in the evaluation of CVD risk, with a recommendation that appropriate referral postpartum by the obstetrician to a primary care physician or cardiologist should occur so that in the years after pregnancy, risk factors can be carefully monitored and controlled (4). However, there is a dearth of evidence to inform optimal monitoring and prevention protocols. The study by Stuart and colleagues makes an important contribution to fleshing out these recommendations. Additional prospective studies with repeatedly measured CVD risk factors in postpartum women are needed to build on the present study findings and to further inform monitoring practices in women with a history of HDP. Cardiovascular disease is the leading cause of death among women in the United States and globally (6), and more than 80% of U.S. women have children (7). Pregnancy may therefore provide an opportunity to identify CVD, intervene, and ultimately reduce the disease burden in women. Stuart and colleagues' findings strengthen the case for investing in this research agenda to reduce the burden of CVD in women.