Preterm birth rates climbed sharply among America’s poorest families over the past decade while remaining flat for wealthier households, revealing a troubling divide that hits Black mothers hardest regardless of income.
Research tracking more than 400,000 mothers from 2011 to 2021 found preterm births jumped from 9.7% to 11.1% in households earning less than the federal poverty level. Families earning between 100% and 199% of poverty saw rates surge from 7.8% to 10.0%. Meanwhile, wealthier families saw virtually no change, holding steady around 8%.
Black mothers faced the highest preterm birth rates across every income bracket. Even affluent Black mothers experienced worse outcomes than poor white mothers, with high-income Black families showing rates higher than white families living below the poverty line.
The disparities run deeper than economics alone. When researchers analyzed both race and income together, racial factors proved so powerful they overshadowed income-based patterns entirely. Black mothers faced a 19% higher risk than white mothers at the lowest income level and 13% higher risk at the highest level.
Preterm birth remains the leading cause of infant death and illness in America. The research team from Boston Medical Center, University of Massachusetts Chan Medical School, and Harvard T.H. Chan School of Public Health suggests that income inequality widened during this period, pointing to systemic racism as a root cause.
The findings suggest public health interventions focusing solely on poverty miss critical factors affecting Black communities, including discrimination in healthcare, chronic stress, and unequal access to quality prenatal care.
See: “Rise of preterm births in US linked to poverty and race” (January 11, 2026)
