BACKGROUND:A mother whose child has a chronic condition, such as a major congenital anomaly, often experiences poorer long-term health, including earlier mortality. Little is known about the long-term health of fathers of infants with a major congenital anomaly.METHODS:In this population-based prospective cohort study, we used individual-linked Danish registry data. Included were all mothers and fathers with a singleton infant born January 1, 1986, to December 31, 2015. Cox proportional hazards regression was used to generate hazard ratios for all-cause and cause-specific mortality among mothers and fathers whose infant had an anomaly and fathers of unaffected infants, relative to mothers of unaffected infants (referent), adjusted for child’s year of birth, parity, parental age at birth, parental comorbidities, and sociodemographic characteristics.RESULTS:In total, 20 952 of 965 310 mothers (2.2%) and 20 655 of 951 022 fathers (2.2%) had an infant with a major anomaly. Median (interquartile range) of parental follow-up was 17.9 (9.5 to 25.5) years. Relative to mothers of unaffected infants, mothers of affected infants had adjusted hazard ratios (aHRs) of death of 1.20 (95% confidence interval [CI]: 1.09 to 1.32), fathers of unaffected infants had intermediate aHR (1.62, 95% CI: 1.59 to 1.66), and fathers of affected infants had the highest aHR (1.76, 95% CI: 1.64 to 1.88). Heightened mortality was primarily due to cardiovascular and endocrine/metabolic diseases.CONCLUSIONS:Mothers and fathers of infants with a major congenital anomaly experience an increased risk of mortality, often from preventable causes. These findings support including fathers in interventions to support the health of parental caregivers.