Maternal ethnicity and birthweight among blacks

This paper examines the association of ethnicity and birthweight, adjusted for other maternal and infant characteristics, among black women who gave birth in Massachusetts from 1987 through 1989. Data are drawn from the standard certificate of live birth, which includes questions on race and ethnicity/ancestry as well as birthweight; maternal sociodemographic and biological characteristics; access to prenatal care; and infant characteristics. The study cohort consists of 18,571 black infants and a comparison group of 206,358 non-Hispanic white infants. Infants whose mothers reported their race as black were further categorized into six ethnic groups: American, Haitian, West Indian, Cape Verdean, Hispanic, and other black. In addition to descriptive analyses, we used multiple linear regression to measure the association between ethnicity, other characteristics, and birthweight; and we used multiple logistic regression to measure the odds ratio of low birthweight (ranging from 500 g to 2499 g) for the six black ethnic groups, adjusted for other characteristics. Results indicate that Americans have lower mean birthweight and generally higher levels of risk than other black ethnic groups. Compared to the reference group of non-Hispanic whites, Americans (OR = 1.49), other blacks (OR = 1.41), and West Indians (OR = 1.37) have significantly elevated relative risks of low birthweight.