Changes of maternal and fetal pituitary-adrenocortical functions during human labour.

The results of maternal 11-hydroxycorticoid (11-OHCS) determination on blood obtained from four stages of 44 spontaneous labour cases showed a strong and time-related maternal adrenocortical activation during vaginal delivery. The high 11-OHCS level in the cord blood and the increase of the 11-OHCS concentration in the amniotic fluid suggested the same response of the fetal adrenal. However, in 14 cases of elective caesarean sections the 11-OHCS levels in the cord blood and the amniotic fluid did not rise in spite of the elevated maternal plasma 11-OHCS content.