Historic redlining negatively impacts maternal health almost a century on

A Home Owners' Loan Corporation map showing the East Bay region and housing redlining from 1937. (Mapping Inequality public domain image)

New research shows that Black and Hispanic women who live in historically redlined neighborhoods are at a greater risk of Severe maternal morbidity (SMM)—a condition that includes multitude of life-threatening pregnancy complications occurring before or after delivery—than other ethnic and racial groups

A study—led by UC Berkeley School of Public Health PhD candidate Xing Gao and published in Paediatric and Perinatal Epidemiology—found that women in areas categorized as “hazardous” by the Home Owners’ Loan Corporation (HOLC) were more susceptible to SMM.

The HOLC was a federal agency created in the 1930s that used maps to rank neighborhoods on a four-point scale, from “A” to “D.” Predominately white, upper-middle class neighborhoods were given A ratings, or “best” scores, and ethnically non-white areas were given D, or “hazardous,” ratings and colored red on maps, a practice known as redlining. Mortgage lenders refused to finance homes  in areas with D grades, which led to decades of disinvestment in predominantly Black, Hispanic, and Asian neighborhoods. Redlining created an unequal distribution of resources across neighborhoods which continues to produce unequal health outcomes, almost a century after it first appeared.

“This finding demonstrates that historical redlining, one of the many mechanisms through which public and private institutions have practiced racial housing discrimination, has lasting impact on the well-being of Black and Latinx birthing people today,” said Gao. “This helps us understand that the persistent racial inequities in pregnancy-related outcomes are produced by discriminatory policies and programs occurring over generations.”

The report used maps from the Mapping Inequality Project, an initiative led by the University of Richmond to digitize HOLC maps across the country. Eight cities in California, including Berkeley, Oakland, and San Francisco, were overlaid on top of census tracts to gather demographic data and compile neighborhood ratings. The results concluded that residency in neighborhoods marked “D” by the HOLC showed greater risk of SMM among Black and Hispanic groups in the present day. Hispanic people were also at greater risk of SMM in “C” neighborhoods.

Gao recommended that future policies address these disparities “through a more structural approach” to alleviate “the cumulative burden” of adverse reproductive health outcomes of Black and brown communities.

Prior studies have examined individual and hospital-level risk factors for SMM, but none had yet looked at redlining as a contributing factor. Housing discrimination did not only take the form of HOLC grades and Gao says that her research captures all but a snippet of the full scope of racism’s health outcomes.

“Housing discrimination did not begin with HOLC’s creation of these redlining maps,” she said. “Rather, the redlining maps capture the racial discrimination that was already happening.”


Authors include Xing Gao, Amani Allen, Rachel Morello-Frosch, Barbara Abrams, and Mahasin S. Mujahid of UC Berkeley School of Public Health; Curisa M. Tucker and Suzan L. Carmichael of Stanford University; Jonathan M. Snowden of Portland State University.

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