The U.S. faces a grave—and worsening—public health challenge when it comes to maternal mortality and morbidity. Despite spending more on maternity care than any other country, the U.S. has the highest rate of maternal mortality (the death of an individual while pregnant or within the first six weeks after pregnancy ends) among high-income countries. While an estimated 700 people die annually from pregnancy-related complications, instances of maternal morbidity—which the Centers for Disease Control and Prevention (CDC) defines as life-threatening complications of childbirth and pregnancy that undermines a pregnant person’s functional ability—is also a public health crisis, and it disproportionately affects people of color. Black women are three times as likely to be affected, and Indigenous women are twice as likely, compared to white women.

Despite the scope and gravity of this public health crisis, previous efforts to explain the factors driving maternal mortality and morbidity have fallen short. A new report conducted through the University of Minnesota School of Public Health (SPH) Minnesota Evidence-Based Practice Center (EPC) aims to fill this gap by undertaking a comprehensive review of academic studies focused on risk factors associated with maternal morbidity and mortality during the prenatal and postpartum periods. The researchers sought to understand population-level increases in maternal mortality and morbidity by examining studies which analyzed social determinants of health. Social determinants of health represent the broader conditions in which people live their lives and include factors like access to healthcare, socioeconomic and educational status, physical environment, and social support networks.

Written by a national team of researchers including SPH Associate Professor Mary Butler, who served as Principal Investigator for the project, the report informed a P2P workshop held to discuss the topic of maternal mortality and morbidity. To compile it, researchers exhaustively searched academic databases for observational studies examining exposures related to social and structural determinants of health and at least one health or healthcare-related outcome for pregnant and birthing people. The main takeaways and recommendations in the report include the following:

• While the studies broadly covered social-structural determinants of health for pregnant and birthing people, the determinants they identified represent only a subset of potential factors of interest and did not address interdependence of risk factors, including biological or medical risk factors.
• The studies reviewed in the report covered maternal risk factors broadly, including identity and discrimination issues, socioeconomic status, violence, trauma, psychological stress, structural/institutional factors, rural and urban differences, environmental conditions, comorbidities, and healthcare use factors.
• However, the limited depth and quality of available research within each risk factor domain—including racism and other forms of discrimination—impeded the researchers’ ability to understand pathways connecting social-structural determinants of health and maternal health outcomes.
• The report found an unexpectedly large volume of research on violence and trauma relative to other potential social determinants of health for pregnant people.
• Among the maternal health outcome categories in the studies (which included hypertensive disorders, gestational diabetes, cardio/metabolic disorders, depression, other mental health or substance use disorders), depression and other mental health outcomes represented a large proportion of the health outcomes captured.

“This systematic review of the evidence helps inform academics, policy makers, health care practitioners and others about the key gaps in our understanding of how we can better prevent instances of maternal morbidity and mortality,” says Butler, who in addition to being principal investigator on the project and a report co-author, is also EPC co-director.

While not meant as a policy recommendation, P2P reports provide organizations with comprehensive, evidence-based information on common medical conditions and new healthcare technologies and strategies. In addition to identifying research gaps in specific scientific areas, P2P reports help to identify methodological and scientific weaknesses, suggest research needs, and move the field forward through an unbiased, evidence-based assessment of the available literature.

The report was commissioned and funded by the NIH Office of Disease Prevention.