Predictive Oestradiol Surge of Premature Labour and its Suppression by Glucocorticoids

Abstract

Summary: Plasma oestradiol‐17β and plasma progesterone levels in premature labour have been compared with those measured serially in 33 primigravidae during normal pregnancy and labour. In 31 of the 38 patients in progressive premature labour, the plasma oestradiol level was 2 S.D. or more above the mean for control patients of similar gestational age and was similar to those patients during labour at term. Levels of plasma progesterone in patients in the premature labour group tended to be below the mean for gestation, although still within the normal range. In 12 patients studied serially, oestradiol levels rose dramatically, high values being detected 9.6 ± 5.2 days preceding parturition; progesterone levels gave no consistent trend. Progressive uterine activity in preterm labour and term labour seems to be associated with a progesterone to oestradiol ratio of 6:1. The steroid profiles of 2 patients in premature labour were studied before and after the administration of betamethasone. Both the premature labour and the elevated plasma oestradiol levels were suppressed by the therapy.