Fetal amino acids in normal pregnacies and in pregnancies complicated by intrauterine growth retardation

Plasma amino acid concentrations were measured in normal (AGA) and intrauterine growth retarded (IUGR) percutaneous umbilical blood sampling (PUBS) performed for prenatal diagnosis or at elective cesarean section. IUGR fetuses present significantly lower concentrations of most amino acids, with a significant reduction of the umbilical veno-arterial difference for total a-amino nitrogen. These findinigs are present early in grwoth retarded fetuses and may be potentially responsible for the growth retardation.