A longitudinal study of plasma and urinary cortisol in pregnancy and postpartum

Abstract

Context: There is a paucity of longitudinal data on plasma and urinary cortisol levels during pregnancy using modern assays. Furthermore, conflicting data exist as to the effect of the low-dose oral contraceptive pill (OCP) on cortisol. Design, Subjects, and Measurements: We conducted a prospective longitudinal study on morning plasma cortisol (total and free), corticosteroid-binding globulin (CBG), and 24-h urinary free cortisol (UFC) levels in 20 pregnant women during the first, second, and third trimesters and 2-3 months postpartum compared with 12 subjects on low-dose OCP and 15 nonpregnant subjects not taking the OCP (control group). Results: A progressive rise in total plasma cortisol,..