Amniotic fluid catecholamines and metabolites in intrauterine growth retardation.

Simultaneous determinations of amniotic fluid levels of the catecholamines dopamine (DA), norepinephrine (NE), and epinephrine (E), and the intraneuronal metabolites of DA, 3,4-dihydroxyphenylacetic acid (DOPAC) and NE, 3,4-dihydroxyphenylglycol (DOPEG), were made, by radioenzymatic assay, in pregnancies resulting in growth-retarded (n = 14) and normal (n = 63) infants. Significant elevations in the mean concentration of NE (p less than 0.000005), E (p less than 0.005), and DOPEG (p less than 0.000001) as well as a significant decrease in the mean concentration of DOPAC (p less than 0.000001) were found in pregnancies resulting in growth-retarded infants as compared to pregnancies resulting in normal infants. Amniotic fluid DOPEG levels were found to be the most discriminative. As amniotic fluid catecholamines are predominantly of fetal origin, these findings suggest that an increase in adrenergic activity and a decrease in dopaminergic activity occur in intrauterine growth retardation as a response to chronic stress.