Abstract
Cord blood levels of arginine vasopressin(AVP)are known to be high after vaginal delivery(VD)in contrast to ceasarian section (C/S)delivery without labor. However, the mechanism, significance, and postnatal duration of the AVP hypersecretion are not known. We studied serial values for AVP concentration by radioimmunoassay in 61 full term and 13 premature (32-36 weeks gestation) infants during the first 24 hours of life. All normal infants had Apgar values >7. Mean AVP values vs time did not differ for premature and full term infants. Paired (mean ± SEM, uU/ml) umbilical artery(UA)and vein(UV)levels following VD and C/S during labor were 90 ± 15 and 15 ± 5.6 respectively(p<.001). Cord UA values for 2 anencephalic infants, 2 infants with breech presentation, and 9 infants delivered by C/S without labor, were significantly lower than values after normal VD and C/S with labor. Plasma AVP after VD or C/S with labor fell rapidly after delivery; peripheral venous levels in VD infants were 22% of UV values by 30 minutes (p<.05). By 2 hours AVP values for all infants approached adult basal levels.
Conclusion: a)Cord blood AVP is of fetal origin since UA>UV, and anencephalic AVP levels are low, b)Premature infants have an intact AVP secretory mechanism, c)Anoxia is not the stimulus for the fetal AVP surge in labor, d)Cerebral compression from VD may be the mechanism of AVP hypersecretion.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hadeed, A., Leake, R., Weitzman, R. et al. 973 MECHANISM OF FETAL VASOPRESSIN HYPERSECRETION DURING THE PERINATAL PERIOD. Pediatr Res 12 (Suppl 4), 526 (1978). https://doi.org/10.1203/00006450-197804001-00979
Issue Date:
DOI: https://doi.org/10.1203/00006450-197804001-00979