Placental abruption and long-term maternal cardiovascular disease mortality: a population-based registry study in Norway and Sweden

Women with preeclamptic pregnancies have increased long-term cardiovascular disease (CVD) mortality. We explored this mortality risk among women with placental abruption, another placental pathology. We used linked Medical Birth Registry and Death Registry data to study CVD mortality among over two million women with a first singleton birth between 1967 and 2002 in Norway and 1973 and 2003 in Sweden. Women were followed through 2009 and 2010, respectively, to ascertain subsequent pregnancies and mortality. Cox regression analysis was used to estimate associations between placental abruption and cardiovascular mortality adjusting for maternal age, education, year of the pregnancy and country. There were 49,944 deaths after an average follow-up of 23 years, of which 5453 were due to CVD. Women with placental abruption in first pregnancy (n = 10,981) had an increased risk of CVD death (hazard ratio 1.8; 95 % confidence interval 1.3, 2.4). Results were essentially unchanged by excluding women with pregestational hypertension, preeclampsia or diabetes. Women with placental abruption in any pregnancy (n = 23,529) also had a 1.8-fold increased risk of CVD mortality (95 % confidence interval 1.5, 2.2) compared with women who never experienced the condition. Our findings provide evidence that placental abruption, like other placental complications of pregnancy, is associated with women's increased risk of later CVD mortality.