FETAL CATECHOLAMINE RELEASE IN RESPONSE TO LABOR AND DELIVERY

  • 1 January 1982
    • journal article
    • research article
    • Vol. 60  (5) , 607-611
Abstract
Umbilical arterial plasma norepinephrine and epinephrine were measured using a sensitive, specific radioenzymatic assay. Plasma catecholamines were correlated with umbilical arterial blood gases, durations of the 1st and 2nd stages of labor, duration of rupture of the membranes, fetal heart rate tracing and fetal sex. Significant correlations were observed for plasma norepinephrine vs. fetal pH and PO2 [partial pressure], and plasma epinephrine vs. pH but not PO2. The majority of the fetal heart rate tracings demonstrated a normal baseline or mild variable decelerations. Plasma catecholamines and blood gases were similar in these 2 groups. Significant elevations of both plasma catecholamines were observed with those tracings commonly associated with fetal distress, but the number of infants was small. No sex differences were observed in plasma norepinephrine or epinephrine or in responsiveness. The human fetus at term responds to acidosis and hypoxia with a graded catecholamine release. This may be an important adaptive mechanism.