Racial and ethnic disparities in the rate of preterm birth (PTB) continue to persist between Black and White women, with the rate of PTB steadily increasing among Black women. Variation exists in the PTB rate among Black women based on nativity. The CDC (2005) reported PTB rate for foreign-born Black women was 13.9% compared to 18.2% for US-born Black women. This proposal addresses a question which heretofore has remained largely unexplored -i.e., the underlying causes and correlates of observed disparities in PTB among foreign-born Black women in the US, and between foreign-born and US-born Black women. The specific research aims of this application are to: 1) compare socio-demographic, psychosocial, and health behavioral characteristics and rates of PTB between foreign-born and US-born Black women in an urban socially disadvantaged population, and 2) explore various exposures (both individual and contextual) and adverse birth outcomes across subgroups of Black women by country of birth, duration of tenure in the US, reason for immigration and experiences of racism. This application for a NINR Mentored Patient-Oriented Research Career Development Award (K23) seeks support to enhance the candidate's research skills to study the complex problem of perinatal racial and ethnic health disparities. Over the next three years the candidate proposes a career development plan of perinatal research mentoring and coursework to receive training in advanced quantitative social epidemiology research methods and analysis to investigate the social determinants contributing to the observed racial and ethnic disparities in adverse perinatal outcomes. The proposed study explores in-depth, exposures that underpin the protective effect of foreign nativity on adverse birth outcomes among Black women in the US. This will guided by a maternal stress biologicalpsychosocial theoretical framework using multi-level data from birth records, census tract data, and then a longitudinal maternal-infant health outcomes study that enrolled women (n=4,879) during their first prenatal visit at publicly funded clinics. Studying this to inform the overall problem of racial disparities of PTB between Black and White women is novel, innovative and an important research strategy to elucidate modifiable factors, for which strategic and tailored interventions could be developed to protect against PTB.