83 - Regional Variation in Preterm Birth Does Not Reduce Persistent Racial Disparities

Publication Number: 3079.83

Danielle Brewer, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States; James Collins, Ann & Robert H. Lurie Children's Hospital of Chicago, chicago, IL, United States; Joe Feinglass, Northwestern University Feinberg School of Medicine, Chicago, IL, United States

Background: Persistent racial disparities in rates of preterm birth (PTB) are well documented, however less is known about how these racial disparities vary regionally, especially given important regional differences in population health status, cultural practices, and policies.

Objective: To determine the extent to which the racial disparity in preterm birth ( < 37 weeks, PTB) between non-Hispanic White and non-Hispanic Black populations differs by region of US residence, using data from the 2022 National Vital Statistics (NVSS) Natality file.

Design/Methods: We used bivariate chi-square tests to analyze the significance of regional differences in outcome disparities across the four US census regions (Northeast, South, Midwest, and West) after adjusting for individual level sociodemographic and clinical risk factors.

Results: We analyzed 2,201,658 US births to non-Hispanic (NH) White and NH Black (1,728,192 vs 473,466) individuals in the US in 2022. NH Black mothers were younger, less likely to be married or college-educated, and more likely to have Medicaid-covered births, use WIC services, and reside in the South compared to NH White mothers. Preterm births occurred in 7.6% of NH White deliveries and 12.3% of NH Black deliveries nationally, representing a 61.8% higher rate among NH Black women, with significant regional differences in PTB rates for each race (Figure 1, Table 2). After adjusting for maternal socioeconomic and clinical characteristics, NH Black women were found to have a higher PTB risk than NH White women in every region. While the Northeast and West had lower rates of PTB, the highest risk was observed among NH Black women in the South, relative to NH White women in the Northeast (RR = 1.64, 95% CI 1.62, 1.67, Table 3).

Conclusion(s): Racial disparities in PTB were largely consistent across the United States, yet absolute PTB rates varied meaningfully by region for women of both races. While there are important regional differences in health status and access to care across the US, these persistent racial disparities likely reflect enduring effects of structural racism, childhood adversity, and incompletely measured social determinants, which have been found to contribute to chronic stress and accelerated biological aging. Our study findings indicate that pronounced regional variation in overall PTB outcomes is not accompanied by substantial reductions in racial inequities.

Racial Differences in Preterm Birth by US Region from the 2022 National Vital Statistics System Natality File*
*All outcome differences by race p<0.001

Adjusted Relative Risk of Preterm Birth by Race and Region*
*Adjusted for age, education, marital status, parity, birth in US, Medicaid coverage, WIC use, previous PTB, BMI, pre-pregnancy diabetes, pre-pregnancy hypertension, and smoking during pregnancy

Regional Differences in Rates of PTB by Race