Gestational Age-specific Cut-off Values Are Needed for Diagnosis of Subclinical Hypothyroidism in Early Pregnancy.
J Korean Med Sci
; 30(9): 1308-12, 2015 09.
Article
em En
| MEDLINE
| ID: mdl-26339172
ABSTRACT
During the first trimester of pregnancy, thyroid-stimulating hormone (TSH) >2.5 mIU/L has been suggested as the universal criterion for subclinical hypothyroidism. However, TSH levels change continuously during pregnancy, even in the first trimester. Therefore the use of a fixed cut-off value for TSH may result in a different diagnosis rate of subclinical hypothyroidism according to gestational age. The objective of this study was to obtain the normal reference range of TSH during the first trimester in Korean gravida and to determine the diagnosis rate of subclinical hypothyroidism using the fixed cut-off value (TSH >2.5 mIU/L). The study population consisted of pregnant women who were measured for TSH during the first trimester of pregnancy (n=492) and nonpregnant women (n=984). Median concentration of TSH in pregnant women was lower than in non-pregnant women. There was a continuous decrease of median TSH concentration during the first trimester of pregnancy (median TSH concentration 1.82 mIU/L for 3+0 to 6+6 weeks; 1.53 mIU/L for 7+0 to 7+6 weeks; and 1.05 mIU/L for 8+0 to 13+6 weeks). Using the fixed cut-off value of TSH >2.5 mIU/L, the diagnosis rate of subclinical hypothyroidism decreased significantly according to the gestational age (GA) at TSH (25% in 3+0 to 6+6 weeks, 13% in 7+0 to 7+6 weeks, and 9% for 8+0 to 13+6 weeks, P<0.001), whereas the diagnosis rate was 5% in all GA with the use of a GA-specific cut-off value (P=0.995). Therefore, GA-specific criteria might be more appropriate for the diagnosis of subclinical hypothyroidism.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Complicações na Gravidez
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Algoritmos
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Tireotropina
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Diagnóstico por Computador
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Idade Gestacional
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Técnicas de Diagnóstico Obstétrico e Ginecológico
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Hipotireoidismo
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
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Female
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Humans
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Pregnancy
País/Região como assunto:
Asia
Idioma:
En
Revista:
J Korean Med Sci
Assunto da revista:
MEDICINA
Ano de publicação:
2015
Tipo de documento:
Article