Ng AT, et al. - In this retrospective community-based cohort study, researchers determined the prevalence, aetiology and clinical outcome of pregnant women with heart failure. Study participants were pregnant women in the Kaiser Permanente Health System between 2003 and 2014. They found that 488 (0.13%) out of 385,935 pregnancies had a diagnosis of heart failure, corresponding to 126 cases per 100,000 pregnancies. The most commonly identified cause of heart failure was peripartum cardiomyopathy. In patients with heart failure, preterm birth and caesarean delivery were commonly reported. Heart failure during pregnancy was found to be related to unfavourable fetal outcomes including prematurity and low birth weight. Despite a low rate of overall mortality, an excess risk of death was noted in pregnant women relative to controls.