Low birth weight across generations.

Objectives: This study sought to determine the relationship between maternal birth weight, prenatal care usage, and infant birth weight.

Methods: Stratified and logistic regression analyses were performed on a dataset of computerized Illinois vital records of White (N = 187, 074) and African-American (N = 58,856) infants born between 1989 and 1991 and their mothers born between 1956 and 1975.

Results: Among White mothers who received adequate prenatal care, the low birth weight (<2500 g) rate was 4% for infants of former low birth weight mothers (N = 5230) compared to 2.1% for infants of former nonlow birth weight mothers (N = 93,011), relative risk equaled 1.9(1.7-2.2); the population attributable risk of maternal low birth weight was 4.1%. Among African American mothers who received adequate prenatal care, the low birth weight rate was 15% for infants of former low birth weight mothers (N = 2196) compared to 7.2% for infants of former nonlow birth weight mothers (N = 14,607), relative risk equaled 2.1(1.9-2.4); the population attributable risk of maternal low birth weight was 10.9%. The maternal-infant birth weight associations were consistent across all maternal age, education, marital status, and prenatal care categories.

Conclusions: Maternal low birth weight is a risk factor for infant low birth weight independent of risk status during the current pregnancy. A greater percentage of low birth weight African American (compared to White) infants are attributable to maternal low birth weight.