title: Urine selenium changes during pregnancy do not correlate with thyroid autoantibodies in a mildly iodine deficient population.
abstract: Selenium (Se) is a key component of iodinases; higher Se levels are associated with lower titers of antithyroid peroxidase antibodies (anti-TPO). Pregnancy exerts profound effects on thyroid function and autoimmunity. To assess the relationship of urine Se levels with thyroid function and autoimmunity in pregnant women residing in Athens, Greece, we studied prospectively 47 euthyroid women in uncomplicated singleton pregnancies (mean age + SD: 30 + 5 years) in each trimester, measuring urine Se levels, urine iodine, plasma thyrotropin (TSH), free thyroxine and triiodothyronine (FT4 and FT3), as well as levels of anti-TPO antibodies. Changes of the measured parameters were assessed over each trimester; thyroid parameters were assessed with relation to Se levels. Urine Se dropped by the third trimester, whereas urine iodine did not change appreciably during pregnancy. TSH and anti-TPO did not show appreciable changes; FT4 and FT3 gradually decreased as the pregnancy advanced. No relationship between urine Se levels and anti-TPO was found. During pregnancy, changes in urine Se levels accompany mild changes in thyroid function. However, we did not find some association between these changes and thyroid autoimmune activity over this period, probably because the effect of Se on thyroid autoimmunity may only become apparent in case of excess Se fortification.
authors.affiliation: Department of Endocrinology, Diabetes and Metabolism, E. Venizelou Hospital, Athens, Greece, ekoukkou@gmail.com.
authors.forename: E
authors.initials: E
authors.lastname: Koukkou
authors.forename: I
authors.initials: I
authors.lastname: Ilias
authors.forename: M
authors.initials: M
authors.lastname: Alexiou
authors.forename: I
authors.initials: I
authors.lastname: Mamali
authors.forename: S
authors.initials: S
authors.lastname: Nicopoulou
authors.forename: M
authors.initials: M
authors.lastname: Alevizaki
authors.forename: K
authors.initials: K
authors.lastname: Markou
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000652:urine*; D005260:Female; D006801:Humans; D007455:Iodine / Q000172:deficiency*; D011247:Pregnancy; D012643:Selenium / Q000652:urine*; D013963:Thyroid Hormones / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D013963:Thyroid Hormones; D007455:Iodine; D012643:Selenium