Trends in severe maternal morbidity following an institutional team goal strategy for disparity reduction

Background

Racial disparities in maternal pregnancy outcomes, specifically in morbidity and mortality, are persistent in the U.S., and a multifaceted approach to mitigating these disparate outcomes is critical. In 2020, our health system committed to reducing severe maternal morbidity (SMM) in Black patients, employing multiple strategic interventions including implicit bias training, regular reporting of a composite SMM metric stratified by race and ethnicity, standardization of best practices, focused efforts for hemorrhage risk reduction, and system-wide team building.

Objective

The goal of this study is to investigate trends in SMM by race across this period of concentrated interventions to improve maternal outcomes overall, and specifically for Black patients.

Study Design

This is a retrospective cohort study evaluating all delivery admissions at an academic, urban, tertiary-care hospital in Philadelphia—one site of a health system encompassing five delivery hospitals—over a 3-year period from 2019 to 2021. Data including patient demographics, clinical features, and outcomes were extracted from the electronic medical record (EMR). Self-reported race was categorized as Black vs non-Black as documented in the EMR. SMM was defined according to established CDC indicators as well as additional codes identified by Vizient for common sources of SMM including hemorrhage, infection, and embolism. Data were analyzed by year with a multivariable logistic regression model including insurance type and obstetric comorbidity index (OB-CMI), a weighted scoring system accounting for numerous chronic medical conditions and antepartum pregnancy complications.

Results

In total, 12,339 deliveries were included, 64.6% (N=8012) of which were to Black patients. Median OB-CMI score was higher for Black patients at 3 (interquartile range [IQR] 1–5) compared to 2 (IQR 1–4) for non-Black patients, P<.01. There was a significant decrease in SMM for the entire cohort over the study period (8.5% in 2019 to 6.5% in 2021, P=.001), driven by a decreased rate specifically among Black patients (8.9% in 2019 to 6.6% in 2021, P=.005) with a nonsignificant decrease for non-Black patients (7.8% in 2019 to 6.3% in 2021, P=.21). The adjusted model similarly demonstrated decreased risk of SMM over time for Black patients (2020 vs 2019 adjusted odds ratio [aOR] = 0.81, 95% confidence interval [CI] 0.69–0.96; 2021 vs 2019 aOR 0.73, 95% CI 0.62–0.86).

Conclusion

Dedicated efforts to improve equity in maternal outcomes over a 2-year period (2020–2021) in this hospital serving a Black patient majority were associated with a significant decline in SMM, especially among Black patients. This finding demonstrates the success of a high-level, coordinated, and systematic approach in reducing SMM and associated disparities, and is highly consequential in light of the ongoing major epidemic of racial disparities in obstetric outcomes.