Malnutrition in the first two years of life. The contribution of low birth weight to population estimates in the United States.

To examine the contribution of low birth weight (LBW) to prevalence estimates of undernutrition as measured by low length-for-age (L/A), we analyzed data on 374554 children under 24 months old from the Centers for Disease Control Pediatric Nutrition Surveillance System. Overall, 9.2% of white, 13.4% of black, and 9.2% of Hispanic children weighed less than 2500 g at birth. The mean prevalence of low L/A during the first two years of life was 10.4%, 12.0%, and 11.7% for whites, blacks, and Hispanics, respectively; the mean proportion of L/A less than the fifth percentile attributable to LBW was 28.9%, 27.6%, and 21.3%. Our results demonstrate the need to consider the LBW prevalence in population estimates of malnutrition since 20% to 40% of the prevalence of low L/A in the first two years of life can be attributable to LBW.