Body composition at birth of growth-retarded newborn infants demonstrating catch-up growth in the first year of life.

Total body, extracellular, and intracellular water volume and solids, determined at birth in a group of newborn infants small for date (n = 10) who demonstrated catch-up growth in the first year of life, were compared to similar measurements in newborn infants appropriate for date (n = 11). No significant differences with regard to body water compartment volumes and solids could be found between the 2 groups. It is concluded that intrauterine growth retardation in infants who are capable of catching up in growth after birth is the result of a proportional reduction of the daily increments in fetal solids and body water.