Maternal growth and fetal growth: pregnancy course and outcome in the Camden Study.

Abstract

The Camden (New Jersey) Study of maternal growth during adolescent pregnancy has demonstrated that even when adolescents have larger pregnancy weight gains than mature women they bear infants of the same or smaller size. Moreover growing adolescents were found to produce infants who weighed an average of 127 g less at birth than infants of already grown adolescents. Also recorded in growing adolescents were significantly lower third-trimester serum concentrations of the nutrients ferritin and folate. Adolescent gravidas growing as indicated by the Knee Height Measurement Device had more than a two-fold increased risk of a high systolic/diastolic (S/D) ratio suggesting that maternal growth influences the vascular resistance of the placenta from the fetal side. A high S/D ratio is associated with impaired blood flow and diminished fetal growth. Overall evidence from the Camden Study suggests a competition between the still-growing mother and her fetus that is present even when the adolescents diet is comparable to that of a pregnant adult the weight gain is sufficient and maternal energy stores as fat are abundant. In this competition the metabolic needs of the mother take precedence over the needs of the fetus. Unlike risk factors associated with maternal social class maternal growth has the potential to occur more frequently among more affluent adolescents.