Reduction in Racial Disparities in Severe Maternal Disparities in Severe Maternal Morbidity from Hemorrhage in a Large-Scale Quality Improvement Collaborative

Background
Eliminating persistent racial/ethnic disparities in maternal mortality and morbidity is a public health priority. National strategies to improve maternal outcomes are increasingly focused on quality improvement collaboratives. However, the effectiveness of quality collaboratives for reducing racial disparities in maternity care is understudied.
Objective
To evaluate the impact of a hemorrhage quality-improvement collaborative on racial disparities in severe maternal morbidity from hemorrhage.
Study Design
We conducted a cross-sectional study from 2011 to 2016 among 99 hospitals that participated in a hemorrhage quality improvement collaborative in California. The focus of the quality collaborative was to implement the national maternal hemorrhage safety bundle consisting of 17 evidence-based recommendations for practice and care processes known to improve outcomes. This analysis included 54,311 women from the baseline period (January 2011 through December 2014) and 19,165 women from the postintervention period (October 2015 through December 2016) with a diagnosis of obstetric hemorrhage during delivery hospitalization. We examined whether racial/ethnic-specific severe maternal morbidity rates in these women with obstetric hemorrhage were reduced from the baseline to the postintervention period. In addition, we conducted Poisson Generalized Estimating Equation models to estimate relative risks and 95% confidence intervals for severe maternal morbidity comparing each racial/ethnic group with white.
Results
During the baseline period, the rate of severe maternal morbidity among women with hemorrhage was 22.1% (12,002/54,311) with the greatest rate observed among black women (28.6%, 973/3404), and the lowest among white women (19.8%, 3124/15,775). The overall rate fell to 18.5% (3553/19,165) in the postintervention period. Both black and white mothers benefited from the intervention, but the benefit among black women exceeded that of white women (9.0% vs 2.1% absolute rate reduction). The baseline risk of severe maternal morbidity was 1.34 times greater among black mothers compared with white mothers (relative risk, 1.34; 95% confidence interval, 1.27–1.42), and it was reduced to 1.22 (1.05–1.40) in the postintervention period. Sociodemographic and clinical factors explained a part of the black–white differences. After controlling for these factors, the black–white relative risk was 1.22 (95% confidence interval, 1.15–1.30) at baseline and narrowed to 1.07 (1.92–1.24) in the postintervention period. Results were similar when excluding severe maternal morbidity cases with transfusion alone. After accounting for maternal risk factors, the black–white relative risk for severe maternal morbidity excluding transfusion alone was reduced from a baseline of 1.33 (95% confidence interval, 1.16–1.52) to 0.99 (0.76–1.29) in the postintervention period. The most important clinical risk factor for disparate black rates for both severe maternal morbidity and severe maternal morbidity excluding transfusion alone was cesarean delivery, potentially providing another opportunity for quality improvement.
Conclusion
A large-scale quality improvement collaborative reduced rates of severe maternal morbidity due to hemorrhage in all races and reduced the performance gap between black and white women. Improving access to highly effective treatments has the potential to decrease disparities for care-sensitive acute hospital-focused morbidities.