Nativity-Related Disparities in Preterm Birth and Cardiovascular Risk in a Multiracial U.S. Cohort

Having a preterm birth is associated with future cardiovascular risk. Non-Hispanic Black women have higher rates of preterm birth than non-Hispanic White and Hispanic women, but nativity-related disparities in preterm birth are not well understood.

Data from 6,096 women in the Boston Birth Cohort: non-Hispanic Black (2,699), non-Hispanic White (997), or Hispanic (2,400), were analyzed in June 2021. Differences in cardiovascular risk factors were assessed. The association of preterm birth with nativity and duration of U.S. residence were investigated using multivariable logistic regression.

U.S.-born women in all 3 racial-ethnic groups had a higher prevalence of obesity, smoking, and severe stress than foreign-born women. Foreign-born non-Hispanic Black and Hispanic women had lower odds of preterm birth than U.S.-born counterparts (non-Hispanic Black: AOR=0.79, 95% CI=0.65, 0.97; Hispanic: AOR=0.72, 95% CI=0.56, 0.93). In all the 3 groups, foreign-born women with shorter (<10 years) duration of U.S. residence had lower odds of preterm birth than the U.S.-born women (non-Hispanic Black: AOR=0.57, 95% CI=0.43, 0.75; Hispanic: AOR=0.72, 95% CI=0.55, 0.94; non-Hispanic White: AOR=0.46, 95% CI=0.25, 0.85), whereas the odds of preterm birth in foreign-born women with ≥10 years of residence were not significantly different.

Foreign-born women had better cardiovascular risk profiles in all groups and lower odds of preterm birth in non-Hispanic Black and Hispanic groups. In all the 3 groups, a shorter duration of U.S. residence was associated with lower odds of preterm birth. Further studies are needed to understand the biological and social determinants underlying these nativity-related disparities and the impact of acculturation.