Oxidative stress biomarkers in amniotic fluid of pregnant women with hypothyroidism.

Purpose: Hypothyroidism in pregnancy is the serious state that may lead to fetal morbidity and mortality. Oxidative stress biomarkers in the amniotic fluid can provide important information on the health, development and maturation of the fetus during pregnancy. In this study, we examined whether maternal hypothyroidism contributes to increased oxidative stress biomarkers in the amniotic fluid during the first trimester of pregnancy. Materials and methods: The study was conducted on healthy pregnant women and pregnant women with hypothyroidism (gestational age: 16-18 weeks). Oxidative stress biomarkers, such as superoxide anion (O2•-), hydrogen peroxide (H2O2), nitric oxide (NO), peroxynitrite (ONOO-), lipid peroxide (LPO), reduced glutathione (GSH) and oxidized glutathione (GSSG) were assayed in the amniotic fluid. Results: The results of this study indicated that concentrations of O2•- and NO are significantly higher, while the concentration of H2O2 is significantly lower in the amniotic fluid of pregnant women with hypothyroidism in comparison to healthy pregnant women. There were no differences in concentrations of LPO, GSH and GSSG among tested groups. Also, we found that amniotic fluid concentration of O2•- is negatively correlated with the body weight and Apgar score values of the newborns. Conclusion: These results suggest that pregnancy hypothyroidism is characterized by the amniotic fluid oxidative stress. Incorporation of the oxidative stress biomarkers measurement in the amniotic fluid may be of clinical importance in the management of pregnancy hypothyroidism.

Effects of maternal subclinical hypothyroidism on amniotic fluid cells oxidative status.

In this study, we researched the effects of maternal subclinical hypothyroidism on the amniotic fluid cells oxidative metabolism during the first trimester of pregnancy. Oxidative stress and damage biomarkers were assayed in the amniotic fluid cells of healthy and pregnant women with subclinical hypothyroidism. Obtained results show that amniotic fluid cells of pregnant women with subclinical hypothyroidism have significantly higher concentrations of oxidative stress biomarkers (superoxide anion, nitric oxide, peroxynitrite) and oxidative damage (lipid peroxide and micronuclei frequency), but lower concentrations of hydrogen peroxide and oxidized glutathione in comparison to healthy pregnant women. We also showed that oxidative stress biomarkers were positively correlated with micronuclei frequency and lipid peroxide concentration in amniotic fluid cells of pregnant women with subclinical hypothyroidism. The present study provides the first evidence for prooxidative effects of maternal subclinical hypothyroidism on the fetus obtained by the estimating oxidative metabolism in the amniotic fluid cells.