Relation of maternal low birth weight to infant growth retardation and prematurity.

OBJECTIVES: This study sought to determine the relationship between maternal birth weight, infant intrauterine growth retardation, and prematurity.
METHODS: Stratified and logistic regression analyses were performed on a dataset of computerized Illinois vital records of African American (N = 61,849) and White (N = 203,698) infants born between 1989 and 1991 and their mothers born between 1956 and 1975.
RESULTS: Race-specific rates of small-for-gestational age (weight-for-gestational age <10th percentile) and preterm (<37 weeks) infants rose as maternal birth weight declined. The adjusted (controlling for maternal age, education, marital status, parity, prenatal care utilization, and cigarette smoking) odds ratio (95% confidence interval) of small-for-gestational age for maternal low birth weight (<2,500 g) among African Americans and Whites were 1.7 (1.1.4-1.9) and 1.8 (1.7-2.0), respectively. The adjusted odds ratio (95% confidence interval) of prematurity for maternal low birth weight (<2,500 g) among African Americans and Whites were 1.6 (1.3-1.9) and 1.3 (1.0-1.6), respectively. The racial disparity in the rates of small-for-gestational age and prematurity persisted independent of maternal birth weight: adjusted odds ratio equaled 2.2 (2.1-2.4) and 1.5 (1.4-1.7), respectively.
CONCLUSIONS: Maternal low birth weight is a risk factor for infant intrauterine growth retardation and prematurity among African Americans independent of maternal risk status during pregnancy; it is a risk factor for infant intrauterine growth retardation among Whites. Maternal low birth weight fails to explain the racial disparity in the rates of small-for-gestational age and premature infants.