Serial estimates of body water content and distribution during the first postnatal month in baboons

Water content of the various body compartments was estimated serially during the first postnatal month in six term baboon neonates. In absolute volumes (mL), total body water, intracellular water, and plasma volume all increased linearly with body weight and postnatal age, although the effect of weight was predominant. In proportion to body weight (mL/kg), total body water, intracellular water, and plasma volume increased linearly with postnatal age whereas extracellular water and red cell volume decreased. There was no linear relation between the proportions of any of the water volumes and body weight.