Postnatal body weight changes were assessed in 99 infants with birth weights of less than 1200 gm. Growth was monitored during the first 50 postnatal days, and two growth curves were generated for comparison with the lowest Dancis grids. Our critically ill infants, in whom parenteral alimentation was a major source of nutrition, closely paralleled the 1000 gm Dancis grid, whereas our infants of approximately 750 gm birth weight did not lose as much weight as predicted by Dancis and gained weight at a faster rate.