Birth weight of US biracial (black-white) infants: regional differences.

OBJECTIVE

The study examined the prevalence of low birth weight among biracial infants of black and white parents, by region of the United States.

METHODS

Using the national linked live birth-death infant file for 1991, low birth weight (<2,500 g) was examined among 50,980 biracial singleton infants according to parental race (black mother-white father vs. white mother-black father).

RESULTS

Nationally, the rate of low birth weight was 31% higher in the black mother-white father group (8.4%) than in the white mother-black father group (6.4%). The difference was smaller in the Northeast, reflecting a high rate (9.8%) for biracial infants of Puerto-Rican white mothers. The difference in the West was larger (75%), due to both a high rate in the black mother-white father group (9.1%) and a low rate for the white mother-black father group (5.2%), and persisted after controlling for parental education and a variety of maternal risk factors.

CONCLUSIONS

Further studies are needed to identify the maternal factors involved in the regional differences in the prevalence of low birth weight among biracial infants.