Fetal plasma cortisol and dehydroepiandrosterone sulfate concentrations in pregnancy and term parturition

OBJECTIVE: To examine if changes in fetal plasma concentrations of cortisol or dehydroepiandrosterone sulfate (DHEAS) levels are associated with human term parturition. METHODS: Umbilical cord plasma cortisol and DHEAS concentrations were measured in 374 singleton pregnancies that delivered at term in the following six groups: group 1, cordocentesis for clinical indications before 36 weeks of gestation (n = 93); group 2, cordocentesis for clinical indications after 36 weeks of gestation (n = 9); group 3, cord blood sampling after elective cesarean section (CS) at term without labor (n = 140); group 4, cord blood sampling after CS at term with early labor (cervical dilatation 36 weeks) but did not increase during active labor; (4) the cortisol/DHEAS ratio (stress index) increased with advancing gestation and with active labor at term. CONCLUSIONS. Human parturition at term is associated with an increase in fetal plasma cortisol and in the cortisol/DHEAS ratio, but not in DHEAS