SERIAL LEVELS OF PLASMA OESTRADIOL-17β AT THE APPROACH OF LABOUR

Abstract

Plasma estradiol-17.beta. concentration was measured serially in 32 women during the last 10 wk of pregnancy. There were 18 primigravidae and 14 multiparae. No statistically significant difference could be demonstrated between the mean estradiol-17.beta. levels at the various stages of pregnancy in the primigravidae and multiparae. The mean plasma concentration of estradiol-17.beta. showed a gradual rise from 19 at week 30 to 31.6 ng/ml at week 40. There was a gradual rise of unconjugated estradiol-17.beta. during the last month of pregnancy rather than a 2-fold increase as reported by Turnbull et al. The progesterone:estradiol ratio did not show any significant change at the approach of labor.