TSH Levels in Relation to Gestation, Birth Weight and Sex

Abstract

Aims: Low birth weight is associated with hypothyroidism and an adverse metabolic profile in later life. Our aim was to examine the relationship between neonatal TSH and birth weight, gestational age and sex. Methods: We compared blood spot filter paper TSH levels with birth weight, gestational age and sex in a 10% sample of infants screened for congenital hypothyroidism at a single centre in Northern England. All gestational ages were included with infants suspected of having congenital hypothyroidism excluded. Results: Data on 1,728 male and 1,662 female infants were analysed. The distribution of TSH was significantly different between males and females, with males having a higher median TSH (0.7 vs. 0.6). Correlations were shown between TSH and birth weight (ρ = –0.07, p = 0.0001) and gestational age (ρ = –0.05, p = 0.008), with the birth weight association remaining independent of gestational age. The functional form of the model suggested that higher TSH in the lowest birth weight categories was responsible for the association between TSH and birth weight. Conclusions: Low birth weight is related to neonatal TSH levels. Further research is required to assess whether this association explains the relationship between higher TSH and an adverse metabolic profile in later life.

Maternal factors and complications of preterm birth associated with neonatal thyroid stimulating hormone

“…However, these studies measured TSH levels around the 6 th day of life, whereas our study measured infants between day of life 1 and 3, but primarily on day 1 of life. Studies examining cord blood levels or levels obtained soon after delivery have observed similar results to ours (5, 6, 25). …”

Newborn Thyroid Stimulating Hormone Levels in Heel Prick Blood at the Yaounde Gyneco-Obstetric and Paediatric Hospital Cameroon

“…This result was different from the one found by Korada et al in United Kingdom where male gender have had a higher median TSH value [23]. This difference can be explained by the high proportion of male gender in their study compared to ours.…”

“…This weak correlation and low-shared variance can be explained by the small size of our sample. This result is opposed to Korada et al findings where higher TSH were found in the lowest birth weight categories [23] This difference can be explained by the fact that all gestational age where included in the study also inclusive of preterm. It is well known that premature babies are high risk of morbidity and mortality, and illness is another shape of stress [25].…”

Avaliação do valor de corte de TSH em amostras de filtro na triagem neonatal para diagnóstico de hipotireoidismo congênito no Programa "Primeiros Passos" - IEDE/RJ

“…Contudo, sugere-se padronizar a época de coleta das amostras, em vez de utilizar valores de corte variados (30,33). Além da coleta muito precoce da amostra de TSH-F, outros podem ser os fatores responsáveis por resultados falso-positivos desse exame, como o caso de prematuridade, gemelaridade ou presença de retardo de crescimento intrauterino (34,35). Em nosso trabalho, não temos o levantamento de todos esses dados.…”