Severe Maternal Morbidity Among Delivery and Postpartum Hospitalizations in the United States

To propose a new standard for monitoring severe maternal morbidity, update previous estimates of severe maternal morbidity during both delivery and postpartum hospitalizations, and estimate trends in these events in the United States between 1998 and 2009.

Delivery and postpartum hospitalizations were identified in the Nationwide Inpatient Sample for the period 1998-2009. International Classification of Diseases, 9 Revision codes indicating severe complications were used to identify hospitalizations with severe maternal morbidity and related in-hospital mortality. Trends were reported using 2-year increments of data.