Studies on serum oestradiol 17β in normal and hypertensive pregnancies: Preliminary results

Abstract

Serum oestradiol 17 β was measured by a radioimmunoassay method as described by Hotchkiss et al. (1971), using antiserum against 6 oxooestradiol succinyl bovine serum albumin conjugate raised in sheep. 158 determinations of serum oestradiol were performed on normal pregnancy cases between the 30th and 42nd wk of gestation. Serial serum oestradiols were assayed in 5 cases of hypertensive disorder of pregnancy in the third trimester. Serum oestradiol 17 β rose from a mean value of 12.01 ± 3.80 ng/ml (± 1 S.D.) at 30 wk of gestation to a peak of 66.72 ± 31.39 ng/ml (± 1 S.D.) at 40 wk. Thereafter serum oestradiol fell to 66.02 ± 26.48 ng/ml (± 1 S.D.) at 41 wk and 42.77 ± 18.53 ng/ml (± 1 S.D.) at 42 wk of gestation. In 3 out of 5 cases of severe hypertensive disorder or pregnancy, which ended in delivery of normal healthy babies, serial serum oestradiol fell within the range of values for normal pregnancy. In 2 hypertensive cases, where the babies showed evidence of intrauterine growth retardation, serial serum oestradiol values were consistently below the range of serum oestradiol for normal pregnancy. Thus serum oestradiol 17 β could be a useful indicator of fetal wellbeing in pregnancies complicated by hypertension.