Extending Postpartum Surveillance Increases Severe Maternal Morbidity Detection

Investigators in Canada report that surveillance limited to labor and delivery captured fewer severe maternal morbidity (SMM) events than surveillance spanning conception through six weeks postpartum.

In a population-based cohort, researchers used linked administrative and clinical registry data to study nearly 1.1 million births in Ontario from 2012–2021.

Across the cohort, the SMM rate was 27.24 per 1,000 births. With surveillance extended through six weeks postpartum, delivery-focused monitoring missed more than 40% of severe pregnancy complication cases identified under the longer window. The study also described when SMM events first occurred: 16% during the prenatal period, 55% during intrapartum care, and 29% in the postpartum window.

The most common SMM events were severe hemorrhage, severe preeclampsia, and sepsis.