Pregnancy, thyroid, and the potential use of selenium.
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ABSTRACT:
SUBMITTER: Hubalewska-Dydejczyk A
PROVIDER: S-EPMC7033058 | biostudies-literature | 2020 Mar
REPOSITORIES: biostudies-literature
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Pregnancy, thyroid, and the potential use of selenium.
Hubalewska-Dydejczyk Alicja A Duntas Leonidas L Gilis-Januszewska Aleksandra A
Hormones (Athens, Greece) 20191113 1
The management of pregnant women is a major concern of health care around the world. There is growing evidence regarding the influence of selenium (Se) on pregnancy and fetus outcomes. However, due to as yet insufficient evidence, lack of measurable markers to assess the effect of Se supplementation on the human metabolism, and Se's narrow therapeutic index, the majority of experts and the current guidelines published by several scientific societies do not recommend the use of Se in pregnancy an ...[more]
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| S-EPMC7109430 | biostudies-literature
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Project description:Selenium (Se), an essential trace element, is inserted as selenocysteine into an array of functional proteins and forms the core of various enzymes that play a cardinal role in antioxidant defense mechanisms, in redox regulation, and in thyroid hormone metabolism. Variations in plasma Se are due to nutritional habits, geographic and ethnic differences, and probably to genetic polymorphisms, the latter still to be conclusively established. Se concentrations were reported to be low in women of reproductive age in the UK, decreasing further during pregnancy, this resulting in low plasma and placental antioxidant enzyme activities. Since low serum Se levels have been found in women with preeclampsia, it has been hypothesized that low maternal Se status during early gestation may be an indicator of preterm birth. Moreover, it is documented that Se administration during pregnancy tendentially reduced the markers of thyroid autoimmunity and the incidence of maternal hypothyroidism in the postpartum period. Importantly, low Se levels in pregnant women affect fetal growth and augment the risk of delivering a small-for-gestational age infant by reducing placental antioxidant defense, while low Se in the third trimester is thought to indicate increased demands by the placenta, an issue which requires further confirmation. There is evidently a need for double-blind, placebo-controlled studies to better determine the efficacy and safety of Se supplementation in pregnancy at high risk for complications, and for measurement of Se levels or of selenoprotein P, the most reliable parameter of Se status, particularly in selenopenic regions.
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