A randomized trial in babies less than 1250 grams compared a daily protein intake in parenteral nutrition of 2.5 grams/kg/day with an intake of 4 grams/kg/day in the first ten days of life. Both groups had similar non-protein intake. Infants were followed until two years of age. Body weight, length, head circumference and scores on the Bayley Scales of Infant Development III were similar in the two groups. Infants receiving the higher intake of amino acids had a lower frequency of hyperglycemia but a higher frequency of elevated blood urea.