PLASMA NORADRENALINE IN NORMAL PREGNANCY AND IN HYPERTENSION OF LATE PREGNANCY

Abstract

Plasma noradrenaline was measured by radioenzymatic assay on 90 occasions in 72 women throughout normal pregnancy. Plasma noradrenaline levels declined as pregnancy advanced. A total of 21 patients who developed hypertension in late pregnancy were found to have plasma noradrenaline levels significantly lower than controls at the same stage of pregnancy. It is concluded that plasma noradrenaline is reduced in hypertension of late pregnancy. This indicates a compensatory reduction in sympathetic nervous system activity.