Severe Maternal Morbidity: Validated Approach for Comorbidity Risk Adjustment

Severe maternal morbidity (SMM) was developed by the CDC to measure potentially life-threatening complications of pregnancy and childbirth. SMM is nearly 100 times more common than maternal death and has also been on the rise nationally. Because it is so much more common than maternal death and can be measured in any administrative dataset, SMM is a promising measure for providing insights about obstetric outcomes and improvement opportunities. However, comparing SMM rates between groups of patients, such as from different hospitals, is challenging because of differences in their underlying health status – referred to as comorbidities. To help overcome this issue, researchers from CMQCC, Stanford University, and the University of California, Berkeley developed and validated an obstetric comorbidity scoring system for predicting SMM and non-transfusion SMM; non-transfusion SMM includes SMM cases in which blood transfusion was not the sole indicator of a severe complication (approximately half of all SMM cases), and is now commonly reported along with SMM by the CDC and others.