Postnatal weight velocity patterns in very low birthweight infants.

The care of very-low-birth-weight infants has improved over the years with continuing changes in medical and nutritional management. In view of these changes, there is a need to study the pattern of postnatal weight gain. Postnatal weight gain patterns of 32 very-low-birth-weight infants were examined during the first two months of life. Their mean gestational age was 29.5 +/- 2.3 weeks and mean birth weight was 1255 +/- 258 grams. The babies were weighed daily and weight changes were expressed in gram/day. All data were accurately recorded. When mean weight gain profiles were obtained by computing increments at 1, 3, 7 and 14 day intervals, the babies weight gain showed a non-linear pulsatile pattern which did not change even after full enteral nutrition had been established. This study demonstrates that weight velocity profile in very-low-birth-weight infants is not linear as expected from available standard curves and these data might therefore be considered while monitoring the adequacy of the increments of the weight gain of the individual subjects.