Comparison of Definitions of Severe Maternal Morbidity: A National Cohort Study Using Administrative Data

The authors aimed to assess the agreement between different definitions of severe maternal morbidity (SMM) and explore how these definitions impact the measurement of ethnic and socioeconomic inequalities in maternal health outcomes. Their analysis of over 5.9 million maternities revealed significant variation in SMM prevalence across definitions and moderate agreement among them, highlighting that many cases were identified by a single diagnostic code, suggesting a need for improved validation of diagnostic criteria to better inform prevention strategies.