Loss of diurnal rhythm in plasma estrone, estradiol, and estriol in women treated with synthetic glucocorticoids at 34 to 35 weeks' gestation

Abstract

In order to examine the effect of endogenous rhythms in fetal and/or maternal adrenal activity on diurnal changes in plasma estrone (E1), estradiol (E2), estriol (E3), and progesterone (P) in women at 34 to 35 weeks' gestation, we measured these steroids in a group of six women in whom the endogenous circadian rhythm in cortisol was absent or had been suppressed by treatment with exogenous synthetic glucocorticoids. All steroids were suppressed, and no diurnal rhythms in E1, E2, E3 or P were found. Suppression of cortisol and estrogens was greater after dexamethasone (Dx) than after a glucocorticoid-equivalent dosage of prednisone (Pd). Loss of the maternal estrogen rhythms seen in normal patients is consistent with the suggestion that such rhythms may be attributable to diurnal changes in maternal and/or fetal adrenal output of potential precursors. The differences in cortisol and estrogen concentrations after Dx and Pd may indicate dissociation of the glucocorticoid (hyperglycemic) and adrenocorticotropic hormone-suppressing activities of these compounds.