PLASMA CONCENTRATIONS OF CORTISOL, PROGESTERONE AND UNCONJUGATED OESTRADIOL AND OESTRIOL IN WOMEN WITH LIVE ANENCEPHALIC FOETUSES BEFORE, DURING AND AFTER LABOUR

Abstract

In 2 women with anencephalic fetuses, the maternal plasma concentrations of cortisol were similar to those in 6 women with normal fetuses (mean .+-. S.D.: 20.3 .+-. 3.2 .mu.g/100 ml before the onset of labor; 43.4 .+-. 15.4 .mu.g/100 ml during labor; 21.7 .+-. 8.1 .mu.g/100 ml 2 h after labor). The cortisol concentrations in the mixed cord blood were 7.0 and 10.0 .mu.g/100 ml, which were significantly lower than those in normal newborn infants (.PI. < 0.05). In 3 women with anencephalic fetuses, the maternal plasma concentrations of estradiol and estriol during labor were very low, range 1.96-5.54 ng/ml and 0.93-3.49 ng/ml, respectively. Estradiol concentrations in the mixed cord blood of 2 of these fetuses were 3.70 and 5.49 ng/ml, which were similar to those in their mothers, while estriol concentrations were 17.00 and 23.40 ng/ml which were higher than those in the mothers. The progesterone concentration was 159.1 .+-. 25.7 ng/ml. During labor no drop in the concentration was found. The mixed cord plasma progesterone concentration was 657.9 .+-. 385.9 ng/ml. There were no differences between the plasma progesterone levels in normal pregnant women and in pregnant women with anencephalic fetuses, or between those in normal newborn infants and those in anencephalic infants. These findings suggest that as far as progesterone is concerned, the human placenta is a unique site of synthesis and this synthesis is under self-control.