Premature delivery, breeched birth and miscarriage can all be caused by thyroid dysfunction during a mother's pregnancy.
Led by Professor Victor Pop, the team from the University of Tilburg in The Netherlands found that women who had lower levels of thyroid hormone T4 were more likely to be carrying their child in an abnormal position in the womb.
Professor Pop said: "We believe that the relationship between thyroid hormone levels and foetal presentation at birth may be explained by recent findings that motor development in children is related to low maternal thyroid hormone concentration during pregnancy.
"It follows that impaired maternal thyroid function could also influence foetal mobility and therefore rotation of the foetus during labour."
He added: "We now need to carry out further studies to examine the relationship between maternal thyroid function and foetal presentation at birth in more detail."
The results of the study were published in the journal, Clinical Endocrinology.
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