Reduced Plasma Corticotropin-Releasing Hormone Levels during Late Gestation in Patients with Intrahepatic Cholestasis of Pregnancy

Abstract

Objective: Intrahepatic cholestasis of pregnancy (ICP) may lead to sudden onset of stillbirth, which most likely is related to uteroplacental insufficiency and dysregulation of the fetal blood supply. The relaxing effect of corticotropin-releasing hormone (CRH) on blood vessels was measured to examine the role of CRH in the pathogenesis of ICP. Methods: Eighty normal pregnant women and 80 ICP patients were divided into four groups of 20 cases, respectively, each based on gestational age from week 34 to 37. Radioimmunoassay was used to measure CRH in plasma samples collected from all of the subjects. Results: Plasma CRH increased markedly from week 34 to 37 in both ICP and healthy patients, but the increase was lower in the ICP group. Plasma CRH was 322 ± 61 pg/ml in mild ICP cases at 37 weeks' compared to 1,066 ± 173 pg/ml in controls (p < 0.05), but only 218 ± 128 pg/ml in severe ICP (p < 0.05). Plasma CRH was significantly lower at all other measured time points in patients with severe ICP. In ICP patients, there was a negative correlation between plasma CRH and total bile acid (TBA). Conclusion: A limited increasing CRH level and negative correlation of CRH with TBA were unveiled in ICP patients.