Serum and urine amino acid patterns during the first month of life in small-for-date infants.

Prenatal nutrition is impaired in small-for-gestational-age infants. Serum amino acids may show some biochemical features related to the nutritional state of these children. We have carried out a study on serum and urine amino acids in 12 small-for-date infants (SFD) and 14 healthy newborns from birth to 1 month of life. SFD infants showed a high serum level of alanine and decreased concentrations of branched chain amino acids, aspartate, cystine and tryptophan at birth. The results are compatible with a protein malnutrition state. Levels of serum amino acids in SFD infants showed no differences in relation to normal infants after 1 month of rehabilitation with a diet consisting of an adapted milk formula.