BIRTH-WEIGHT ASSOCIATED WITH LOWEST NEONATAL-MORTALITY - INFANTS OF ADOLESCENT AND ADULT MOTHERS

Objective. We tested the hypothesis that survival is highest for infan ts born in the same weight range whether mothers are adolescent or adu lt, comparing the weights at which infants of these mothers achieve lo west neonatal mortality.Methods. The relationship between birth weight and neonatal mortality was studied in births to 16.4 million women us ing the National Center for Health Statistics 1983-1987 national linke d birth/infant death data sets. Neonatal mortality rates were calculat ed for 500 g birth weight categories. Births for maternal ages less th an or equal to 15 years, 16 years, and 17 to 18 years were compared wi th births to adults 19 to 34 years of age, whites and blacks considere d separately. The birth weight categories associated with minimum neon atal mortality and the weight range corresponding with greatest surviv al were determined for each age and racial group. Results. Minimum neo natal mortality rates occurred at the same birth weights (3500 to 4499 g white and 3000 to 3999 g black) whether mothers of the infants were adolescents or adults. The most favorable range of birth weight, in w hich survival was greatest, commenced at 3000 g for all mothers, termi nating at 3999 g for most black adolescents and black adults, 4499 g f or most white adolescents, and 4999 g for white adults. Of infants bor n to mothers less than or equal to 16 years old, 33% were lighter and 1.5% were heavier than the favorable birth weight range. Conclusion. T he birth weight categories with minimum neonatal mortality and the bir th weight range in which neonatal survival was greatest were comparabl e for infants of adolescents and adults. Lower birth weights, occurrin g more frequently in births to teenage mothers, were associated with h igher neonatal mortality. Assisting adolescent mothers to bear infants with birth weights in the range corresponding with low neonatal morta lity is an appropriate goal of clinical management.