Eight pre-terms, five with postnatal asphyxia, two hypotrophic newborns and one term infant with severe postnatal asphyxia (mean birth weight 2317 g) were fed in addition to oral nutrition partialy parenterally with glucose solution and a mother-milk adapted amino-acid solution during their first three days of life. At increasing protein supplies with a parenteral share of more than 50% during the three days, the N balances resulted positive on all days although the calories supplied were far below the postulated optimum. On days two and three N retention was about 60% of the supply. Every four hours after discontinuation of the total 16 hours' amino-acid infusion the amino acid levels in plasma were controlled by means of column chromatography. The resulting mean values did not show any imbalances of the amino-acid homeostasis. The maximum mean loss in weight of the present group was 4% of their birth weight during the first ten days of life and thus equalled the loss in weight of normal, healthy pre-terms. Clinical and chemical paramters did not reveal any disadvantageous side effects of parenteral nutrition.