Adolescent pregnancy: associations among body weight, zinc nutriture, and pregnancy outcome

Abstract

In a double-blind zinc trial in low-income, pregnant adolescents thought to be at risk for poor zinc nutriture, subjects were randomly assigned to receive 30 mg zinc (gluconate) or placebo. Response to zinc was related to maternal weight. Infants of normal-weight mothers given zinc had reduced rates of prematurity (p = 0.05) and assisted respiration (p = 0.006). Underweight multiparas given zinc had longer gestational lengths (p = 0.008) than did subjects given the placebo. Multiple stepwise regression analysis, used to identify predictors of infant size, revealed that 14-26% more variance was accounted for in the zinc than in the placebo group. Except for gestational age, the predictors selected were entirely different in the two groups. The zinc group had a positive toxemia screen more often, which did not appear to affect outcome. Zinc supplementation improved pregnancy outcome in normal-weight women and in underweight multiparas. The nonresponse in underweight primiparas was perhaps due to multiple limiting factors.