Plasma ACTH and cortisol during spontaneous and PGF2 alpha-induced labor
Leonardi, R.; Costa, G.; Abate, F.; De Pasquale, R.
Bollettino della Societa Italiana di Biologia Sperimentale 54(19): 1847-1853
1978
ISSN/ISBN: 0037-8771 PMID: 223607 Document Number: 137713
Blood values of ACTH and cortisol were studied in 24 normal young pregnant women. Labor proceeded spontaneously in 13 subjects, and was induced by infusions of PGF2.alpha. in 11. Blood samples were collected at onset of labor or, in the PG induction patients, immediately before the infusion was given, then at intervals during labor, parturition and thereafter. ACTH levels increased progressively in spontaneous labor, the rise becoming statistically significant after the 6th h of labor up to actual parturition, dropping to initial levels 1 h after birth. In the group in which labor was induced with PGF2.alpha., basal ACTH levels were lower, otherwise a continuous rise occurred as before up to parturition at levels considerably higher than in spontaneous labor, declining after birth to levels that were still higher than initial values. Cortisol levels rose and fell similarly in spontaneous labor, while in patients stimulated with PGF2.alpha., basal values of cortisol were lower, then rose progressively during labor and fell after birth to levels that were still higher than basal values. While labor and parturition are undoubtedly forms of stress, the response to this stress on the part of ACTH and cortisol is rather different from that seen in ordinary stress because of the more rapid return to pre-stress values in the parturition. This different effect may be caused by PG, whether administered or endogenous.