The Black-White Disparity in Preterm Birth: Race or Racism?

Centennial Issue
Health Equity Racism

Policy Points:

  • Racism is an upstream determinant of health that influences health through many midstream and downstream factors. This Perspective traces multiple plausible causal pathways from racism to preterm birth.
  • Although the article focuses on the Black-White disparity in preterm birth, a key population health indicator, it has implications for many other health outcomes.
  • It is erroneous to assume by default that underlying biological differences explain racial disparities in health. Appropriate science-based policies are needed to address racial disparities in health; this will require addressing racism.

Preterm birth (PTB)—birth before 37 completed weeks of pregnancy—is among the most important indicators of a population’s health. It is the second most common cause of infant mortality in the US population overall1 and the leading cause among African Americans.2 PTB has serious adverse consequences not only in infancy but across the life course; it is a major cause of childhood developmental disability3 and a strong predictor of chronic disease in adulthood.4,5 A large racial disparity in PTB has persisted for decades, with rates among African American/Black women approximately 1.5 to 1.6 times those among European American/White women.6

Unfortunately, the causes of both PTB and the racial disparity in PTB—which are not necessarily the same—are not well established. Despite lack of evidence and/or evidence to the contrary, widespread assumptions have been made about the racial disparity in PTB; as with many health outcomes, “race” has often been assumed by default and without evidence to reflect differences in underlying biology or behaviors.7–9 Evidence has been mounting over the past two decades that calls those assumptions into serious question, however, pointing to racism as a highly plausible upstream—i.e., fundamental—cause of the Black-White disparity in PTB.10

This paper briefly reviews the evidence about biologically plausible causes of the racial disparity in PTB, focusing on racism and associated racial differences in experiences and exposures that are rarely measured in health studies. The terms “race” and “racial” are used here to refer to social groupings according to the large geographic area (often a continent) of an individual’s ancestry. Geographic ancestry often correlates with observable superficial secondary physical characteristics such as skin color, facial features, or hair texture and with differences in the way that people are treated, but has not been associated with fundamental biological differences.11–16

Open Access


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Braveman P. The Black-White Disparity in Preterm Birth: Race or Racism? Milbank Q. 2023;101(S1): 356-378.