An Evidence Map for Social and Structural Determinants for Maternal Morbidity and Mortality A Systematic Review

OBJECTIVE: To identify the social-structural determinants of health risk factors associated with maternal morbidity and mortality in the United States during the prenatal and postpartum periods. DATA SOURCES: We searched MEDLINE, CINAHL, and Social Sciences Citation Index through November 2022 for eligible studies that examined exposures related to social and structural determinants of health and at least one health or health care-related outcome for pregnant and birthing people. METHODS OF STUDY SELECTION: After screening 8,378 unique references, 118 studies met inclusion criteria. TABULATION, INTEGRATION, AND RESULTS: We grouped studies by social and structural determinants of health domains and maternal outcomes. We used alluvial graphs to summarize results and provide additional descriptions of direction of association between potential risk exposures and outcomes. Studies broadly covered risk factors including identity and discrimination, socioeconomic, violence, trauma, psychological stress, structural or institutional, rural or urban, environment, comorbidities, hospital, and health care use. However, these risk factors represent only a subset of potential social and structural determinants of interest. We found an unexpectedly large volume of research on violence and trauma relative to other potential exposures of interest. Outcome domains included maternal mortality, severe maternal morbidity, hypertensive disorders, gestational diabetes, cardiac and metabolic disorders, weathering depression, other mental health or substance use disorders, and cost per health care use outcomes. Patterns between risk factors and outcomes were highly mixed. Depression and other mental health outcomes represented a large proportion of medical outcomes. Risk of bias was high, and rarely did studies report the excess risk attributable to a specific exposure. CONCLUSION: Limited depth and quality of available research within each risk factor hindered our ability to understand underlying pathways, including risk factor interdependence. Although recently published literature showed a definite trend toward improved rigor, future research should emphasize techniques that improve the ability to estimate causal effects. In the longer term, the field could advance through data sets designed to fully ascertain data required to robustly examine racism and other social and structural determinants of health, their intersections, and feedback loops with other biological and medical risk factors.