Maternal thyroid dysfunction during pregnancy is associated with neurodevelopmental impairment in the offspring. No data are currently available for the offspring of patients treated early for congenital hypothyroidism (CH). The aim of this study was to investigate motor and language milestones at one year of age in a population-based registry of children born to young women with CH.
Design and methods
We assessed 110 children born to mothers with CH, and 1367 children from the EDEN French population-based birth cohort study prospectively, at the age of one year, with identical questionnaires. Outcomes were assessed in terms of scores for childhood developmental milestones relating to mobility, motor coordination, communication, motricity and language skills.
After adjustment for confounding factors, children born to mothers with CH were found to have a higher risk of poor motor coordination than those of the EDEN cohort (OR: 4.18, 95% CI: 2.52–6.93). No differences were identified for the other four domains investigated. Children born to mothers with gestational diabetes have a higher risk of low motor coordination score than their peers (OR: 2.10, 95% CI: 1.21–3.66). Children born to mothers with TSH ≥ 10 IU/L during the first six months of pregnancy were more likely to have low motricity or communication skills scores than those born to mothers with lower TSH concentrations (56% vs 21% for each score, P < 0.04).
Maternal CH may have slight adverse effects on some developmental milestones in the child at one year of age, particularly for children born to mothers with uncontrolled hypothyroidism. However, it remains unclear whether these adverse effects modify subsequent neurodevelopment.