title: Normal intellectual development in children born from women with hypothyroxinemia during their pregnancy.
abstract: Proper maternal thyroid function is known to be essential for neural differentiation and migration in the fetus during the first half of pregnancy. The objectives of this study were to assess the relationship between thyroxin levels, in pregnant women with no thyroid disease and the intellectual development of their offspring in a non-iodine-deficient area, and to know specifically whether or not isolated hypothyroxinemia during pregnancy was associated with a lower intelligence in the offspring. Previously we had publicated values TSH, FT4, free T3 (FT3), anti-thyroid peroxidase antibodies (TPO Abs) and urinary iodine concentration (UIC) in 1322 pregnant women in our hospital area. Now we presented results of intelligence quotient in children born from these pregnancies. We assessed 455 children at one year of age using Brunet-Lezine scale. Of these, 289 children were evaluated again at 6-8 years of age using the WISC-IV. From the total group of children recruited, we established as control subgroup, children born of rigorously normal pregnancies (women with UIC > 150 μg/L, FT4>10th percentile and TPO-Ab negative in both trimesters). The remaining children were divided into two subgroups: those born to mothers with FT4 below the 10th percentile and the rest. No correlation was found between FT4 maternal levels, in either of trimesters studied, and the intellectual scores of offspring. No differences were found in intellectual scores comparing children born to mothers with hypothyroxinemia and those whose mothers were euthyroxinemic in both trimesters, or with the control subgroup. As conclusions we did not find any association between the levels of maternal FT4 during pregnancy and the subsequent intellectual development the offspring from these pregnancies. We attribute this result to the fact that all the pregnant women included had normal thyroid function.
authors.affiliation: Paediatric Endocrinology Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain. Electronic address: MARIAGEMA.GRAUBOLADO@osakidetza.net.
authors.forename: Gema
authors.initials: G
authors.lastname: Grau
authors.affiliation: Paediatric Endocrinology Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Anibal
authors.initials: A
authors.lastname: Aguayo
authors.affiliation: Paediatric Endocrinology Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Amaia
authors.initials: A
authors.lastname: Vela
authors.affiliation: Biochemistry Laboratory, BioCruces Health Research Institute, Hospital Universitario Cruces, UPV/EHU, BioCruces, Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Angeles
authors.initials: A
authors.lastname: Aniel-Quiroga
authors.affiliation: Public Health Laboratory Standards, Basque Government Department of Health, Parque Tecnológico de Bizkaia, Ibaizabal Bidea, 48160 Derio, Bizkaia, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Espada
authors.affiliation: Bilbao, Bizkaia, Spain.
authors.forename: Gorka
authors.initials: G
authors.lastname: Miranda
authors.affiliation: Clinical Epidemiologic Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain.
authors.forename: Lorea
authors.initials: L
authors.lastname: Martinez-Indart
authors.affiliation: Paediatric Endocrinology Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Martul
authors.affiliation: Research Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Castaño
authors.affiliation: Paediatric Endocrinology Unit, BioCruces Health Research Institute, Hospital Universitario Cruces, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Plaza de Cruces s/n, 48903 Barakaldo, Bizkaia, Spain; CIBERER (Center for Biomedical Research on Rare Diseases), Carlos III Health Institute, Madrid, Spain.
authors.forename: Itxaso
authors.initials: I
authors.lastname: Rica
mesh_terms: D002648:Child; D002657:Child Development; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood; D007223:Infant; D008607:Intellectual Disability / Q000209:etiology; D007360:Intelligence; D008297:Male; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D013974:Thyroxine / Q000097:blood*
chemical_list: D013974:Thyroxine
keywords: Children; Hypothyroxinemia; Intellectual development; Thyroid