CIRCULATING ANTIDIURETIC HORMONE DURING LABOUR AND IN THE NEWBORN

Abstract
Leung, A., McArthur, R., McMillan, D., Ko, D., Deacon, J., Parboosingh, J. and Lederis K. (the Divisions of Paediatrics, Pharmacology and Obstetrics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada). Circulating antidiuretic hormone during labour and in the newborn. Acta Paediatr Scand, 69: 505, 1980.—Using a high specificity radioimmunoassay, antidiuretic hormone (ADH) concentrations were measured in the plasma of 33 expectant mothers during labour, in cord arterial and venous plasma of their infants at the time of delivery (19 delivered vaginally; 14 delivered by Cesarean section) and in the plasma of the same infants in the first few days of life. Extremely high concentrations of ADH (about 50 times higher than adult basal concentrations) were present in cord arterial blood indicating active fetal production of ADH. Plasma ADH decreased rapidly within an hour after birth and usually fell to adult basal levels during the first day of life. Stressed babies and babies subjected to difficult deliveries had higher plasma levels of ADH.