Maternal and fetal plasma concentrations of endothelin, lipidhydroperoxides, glutathione peroxidase and fibronectin in relation to abnormal umbilical artery velocimetry.

Objective: To study plasma concentrations of endothelin (ET), lipidhydroperoxides (LOOH), glutathione peroxidase (GSHpx) and fibronectin in relation to abnormal umbilical artery velocimetry.
Study Design: Plasma concentrations of ET, LOOH, GSHpx and fibronectin were measured in fetal and maternal venous blood in: (i) a control group (n=10); (ii) in pregnancies complicated by intrauterine growth retardation (IUGR) (n=6) or preeclampsia (n=5) with positive end diastolic flow; and in (iii) pregnancies complicated by absent or reversed end diastolic (ARED) flow in the umbilical artery (n=18). All children were delivered by primary caesarean section.
Results: The significantly highest maternal and fetal ET concentrations were found in plasma collected in pregnancies complicated by ARED flow in the umbilical artery. Maternal fibronectin levels were significantly raised in the ARED flow group. Maternal plasma ET levels were lowest in pregnancies complicated by IUGR. The maternal and fetal plasma concentrations of LOOH and GSHpx did not differ significantly between the groups.
Conclusion: Abnormal Doppler velocimetry, especially ARED flow is associated with elevated maternal and fetal plasma levels of ET. The exact mechanism causing the placental vasoconstriction is unknown yet, but oxidative stress seems not to be involved.