Low Birth Weight
*The percentage of low-birth-weight (LBW) infants ( <2500 grams or 5 pounds, 8 ounces) increased by 11.8% between 1980 and 2000. During that same period, the percentage of very low-birth-weight (VLBW) infants (<1500 grams or 3 pounds, 4 ounces) increased 24.3%.
*During the 1990s, the black-white disparity in LBW and VLBW infants decreased slightly. However, these changes were due in part to greater increases in LBW and VLBW percentages among white infants, not large decreases in LBW and VLBW among blacks. Blacks continue to have a 2- to 3-fold greater risk than whites of giving birth to LBW and VLBW infants.
*The two-decade increase in low birth weights was 14.0% for whites vs. 2.4% for blacks and in very low birth weights was 26.7% for whites and 23.8% for blacks.
*The recent increases in LBW and VLBW among whites are probably due to increases in preterm delivery and changes in obstetrical practices and induction of labor. Another factor may be increased multiple births from assisted reproductive therapies, which often result in LBW infants.
*Mortality rates for specific birth weights declined 47% for infants who were medium-birth-weight (1500-2499 grams) infants and 38% for infants who were very-low-birth-weight (<1500 grams). However, these rates varied by race, with greater decreases for the white infants.
*The reasons for these black-white disparities are complex and are not entirely explained by demographic risk factors such as maternal age, education, or income. Prevention strategies should emphasize research aimed at preventing preterm deliveries and associated factors (e.g., infection). Effective, culturally sensitive intervention programs are also needed.
Contact: Laura Leathers
CDC, National Center for Chronic Disease Prevention
and Health Promotion
(770) 488-5131