Early oxidative stress in amniotic fluid of pregnancies with Down syndrome

Objective: Some evidence suggests that oxidative stress, due to an imbalance between oxidants and antioxidants, occurs in babies with Down syndrome (DS). This study tests the hypothesis that oxidative stress occurs early in DS pregnancies. Design and methods: Isoprostanes (IPs), a new marker of free radical-catalyzed lipid peroxidation, were measured in amniotic fluid from pregnancies with normal, growth restricted and DS fetuses, diagnosed by karyotype analysis of amniotic cells cultured. Results: A nine-fold increase in IP concentrations was found in amniotic fluid of pregnancies with DS fetuses. This increase (595.15; 542.96-631.64 pg/ml, median; 95% CI), was greater than in pregnancies with fetal growth-restricted fetuses (155; 130.57-172.23 pg/ml, median; 95% CI) and normal fetuses (67; 49.82-98.38 pg/ml, median; 95% Cl; p < 0.0001). Conclusions: The study reveals that oxidative stress occurs early in pregnancy and supports the idea of testing whether prenatal antioxidant therapy may prevent or delay the onset of oxidative stress diseases in the DS population. (c) 2006 The Canadian Society of Clinical Chemists. All rights reserved.