Thyroid hormones – Importance for the foetal brain The thyroid gland is a very important but poorly understood organ. EU-funded researchers are investigating the impact of poor maternal supply of thyroid hormones to the foetal brain. Health © Thinkstock Babies with poor thyroid hormone distribution in their brain while in the womb tend to have issues such as reduced IQ, mental retardation and spasticity. Researchers have demonstrated that certain antiepileptic drugs (AEDs) consumed by pregnant mothers can affect thyroid hormone distribution to the foetal brain. Under the aegis of the FETAL THYROXINE (Cognitive adverse effects of in utero exposure to medications: Role for impaired delivery of thyroid hormones into the fetal brain) project, researchers are studying the impact of AEDs on thyroid hormone distribution in pregnant women and their foetuses. Researchers are carrying out in vitro, ex vivo and in vivo studies to determine how AEDs modulate placental transport of thyroid hormones. Preliminary results from the in vivo studies suggest that AEDs impair placental barrier integrity. This in turn alters the expression of transporters involved in thyroid hormone distribution from the mother to the foetus. Future activities entail in-depth studies on placental samples as well as further analysis of ongoing experiments. Research outcomes will shed light on potential risks of AED therapy for pregnant women on foetal development. Clinical application of the tools developed during this study could prevent poor foetal brain development via appropriate monitoring of maternal drug consumption and foetal thyroid hormone concentration. Keywords Thyroid hormones, foetal brain, antiepileptic drugs, pregnant women, placental
