Journal of Clinical Endocrinology & Metabolism, Vol 49, 429-434, Copyright © 1979 by Endocrine Society

ARTICLES

Oxytocin in maternal circulation and amniotic fluid during pregnancy

MY Dawood, O Ylikorkala, D Trivedi and F Fuchs

Oxytocin (OT) was measured by a specific and sensitive RIA in plasma and amniotic fluid throughout pregnancy. OT was detectable in 84.5% of 362 maternal plasma samples and showed a slow and fluctuating increase towards term with a significant sharp peak at 39 weeks of gestation. There was a highly significant correlation between mean plasma OT and the week of gestation (r = 0.5419, P less than 0.005). The minute to minute variability in plasma OT during pregnancy and labor in 7 subjects showed episodic release of OT with two or three spurts per 10 min, with the amplitude of the spurts being greater during labor. Serial maternal plasma OT throughout pregnancy in 10 patients revealed good concentrations of OT (greater than 10 pg/ml) in patients who subsequently had spontaneous labor and no intrapartum uterine dysfunction. Poor (less than 10 pg/ml) or undetectable OT levels were found in patients who subsequently developed intrapartum uterine dysfunction which necessitated cesarean section. OT was detectable in 89.7% or 87 amniotic fluid samples, with a mean +/- SE of 7.8 +/- 3.6 pg/ml at 14--15 weeks, 43.9 +/- 14.7 pg/ml at 40 weeks, and 30.8 +/- 10.5 pg/ml at 41--42 weeks. The significance of these findings is discussed in relation to the role and origin of OT in pregnancy and parturition.

This article has been cited by other articles:

				A. Fuchs, F Fuchs, P Husslein, M. Soloff, and M. Fernstrom Oxytocin receptors and human parturition: a dual role for oxytocin in the initiation of labor Science, March 12, 1982; 215(4538): 1396 - 1398. [Abstract] [PDF]