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CC BY 4.0 · Rev Bras Ginecol Obstet 2022; 44(10): 909-914
DOI: 10.1055/s-0042-1756147
Original Article
Obstetrics

Nutritional Status of Iodine in a Group of Pregnant Women from the State of Minas Gerais Correlated with Neonatal Thyroid Function

Status nutricional de iodo em um grupo de gestantes mineiras correlacionado com função tireoidiana neonatal
Natália Campos Gonçalves Scherr 
1   Departamento de Ginecologia e Obstetrícia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
,
Anelise Impelizieri Nogueira 
1   Departamento de Ginecologia e Obstetrícia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
,
Kamilla Maria Araújo Brandão Rajão 
1   Departamento de Ginecologia e Obstetrícia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
,
Henrique Vitor Leite 
1   Departamento de Ginecologia e Obstetrícia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Abstract

Objective To evaluate the iodine sufficiency of pregnant women assisted in a University Hospital of Minas Gerais, and to correlate the urinary concentrations of maternal iodine with the fetal thyroid hormone levels at birth.

Methods Urinary iodine concentrations from 30 pregnant women with a singleton pregnancy and gestational age lower than 20 weeks were analyzed. Occasional samples of the mothers' urine were collected for the urinary iodine concentration dosage, and these were correlated with the newborns' thyroid-stimulating hormone (TSH) levels.

Results The median iodine urinary concentration of this study's pregnant women population was 216.73 mcg/l, which is proper for the group, following the World Health Organization (WHO). No cases of neonatal hypothyroidism were reported in the study, which corroborates the iodine sufficiency in this population sample.

Conclusion This study shows that despite the increased demand for iodine from pregnant women and the Brazilian Health Regulatory Agency (ANVISA) recommendation of 2013 for reduction of salt iodization levels, the population of pregnant women attended in the prenatal ambulatory of normal risk from the Federal University of Minas Gerais is considered sufficient in iodine. As a higher sample is necessary for the confirmation of these findings, it is too early to recommend the universal supplementation of iodine for Brazilian pregnant women, and more studies must be carried out, considering that iodine supplementation for pregnant women in an area of iodine sufficiency is associated to the risks of the fetus's excessive exposure to iodine.

Resumo

Objetivo Avaliar a suficiência iódica de gestantes atendidas em um Hospital Universitário de Minas Gerais e correlacionar as concentrações urinárias de iodo materno com os níveis de hormônios tireoidianos fetais ao nascimento.

Métodos Foi analisada a concentração urinária de iodo de 30 gestantes com gestação única e idade gestacional menor que 20 semanas. Foram coletadas amostras ocasionais de urina materna para dosagem da concentração urinária de iodo, e estas foram correlacionadas com os níveis de hormônio estimulante da tiroide (TSH) dos recém-nascidos.

Resultados A mediana da concentração urinária de iodo das gestantes estudadas foi de 216,73 mcg/L, sendo adequada para o grupo segundo a Organização Mundial de Saúde (OMS). Não houve nenhum caso de hipotireoidismo neonatal no estudo, o que corrobora a suficiência de iodo nesta amostra populacional.

Conclusão Esse estudo demonstra que apesar do aumento da demanda de iodo pelas gestantes e da recomendação da Agência Nacional de Vigilância Sanitária (ANVISA) de 2013 da redução dos níveis de iodação do sal, a população de gestantes atendidas no ambulatório de pré-natal de risco habitual da Universidade Federal de Minas Gerais é considerada suficiente em iodo. Apesar de uma maior amostragem ser necessária para a confirmação destes achados, é cedo para recomendar a suplementação universal de iodo para as gestantes brasileiras e mais estudos precisam ser realizados, levando-se em conta que a suplementação de iodo para gestantes em áreas suficientes em iodo está associada aos riscos da exposição excessiva de iodo ao feto.

Keywords

urinary iodine - iodine sufficiency - iodine - pregnancy

Palavras-chave

iodúria - suficiência iódica - iodo - gestação

Contributors

All of the authors contributed with the project and data interpretation, the writing of the article, the critical review of the intellectual content, and with the final approval of the version to be published.




Publication History

Received: 17 August 2020

Accepted: 17 December 2020

Article published online:
29 November 2022

© 2022. Federação Brasileira de Ginecologia e Obstetrícia. This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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