Postpartum Haemorrhage and Long-Term Mortality.

Background: Postpartum haemorrhage (PPH) is associated with significant short-term morbidity and mortality. Whether PPH confers long-term all-cause mortality risk is unknown.

Objective: To examine the risk of long-term mortality associated with PPH.

Methods: The Collaborative Perinatal Project (CPP) Mortality Linkage Study is a prospective cohort study of pregnant persons (1959-1966) linked with vital status from the National Death Index and Social Security Death Master File for vital status through 2016. Postpartum haemorrhage was defined based on documentation of haemorrhage within or after 24 hours of delivery in obstetric records. We used Cox regression to examine associations of PPH with long-term all-cause mortality. All models adjusted for delivery characteristics, comorbid medical diagnoses, and sociodemographic characteristics. We further explored heterogeneity in all-cause mortality by sociodemographic characteristics.

Results: Of the 43,583 participants with a singleton pregnancy, 1532 (3.5%) experienced PPH, and 17,165 (39.4%) had died by 2016. The median follow-up time was 52 years (interquartile range 45-54). PPH was associated with increased all-cause mortality risk in unadjusted models (hazard ratio [HR] 1.12, 95% confidence interval [CI] 1.04, 1.21) but not in fully adjusted models (HR 1.02, 95% CI 0.94, 1.11). While HRs varied across sociodemographic subgroups, results were imprecise. We found no evidence of increased cause-specific mortality risk associated with PPH.

Conclusions: Although PPH is associated with short-term morbidity and mortality, our results are generally reassuring against the increased risk of long-term mortality associated with PPH.