Neighborhood ethnic density and preterm birth across seven ethnic groups in New York City

Residential segregation limits non-white ethnic groups' access to white neighborhood resources, but may also reduce their exposure to discrimination and facilitate social support. We computed adjusted preterm birth risk differences (RDs) for seven ethnic groups comparing >25% to ≤25% ethnic density neighborhoods using 1995–2003 New York City birth records and a spatial ethnic density measure. RDs ranged from −15.0 per 1000 (95% CI: −18.5, −11.4) for whites to 6.4 per 1000 (95% CI: 2.8, 9.9) for blacks, with Hispanic and Asian estimates falling in between but tending to be protective. Results suggest that ethnic density is uniquely harmful for non-Hispanic blacks.