Women are more likely to struggle in labour if they have “low to normal” levels of a hormone made by the thyroid gland, suggestes a study.
It is already known that complications can occur, increasing the risk of premature birth or miscarriage, if the levels of the thyroid gland hormone thyroxine are considered too little.
But “low to normal” levels of the hormone could also be dangerous, according to a Dutch team of scientists writing in the journal Clinical Endocrinology.
The University of Tilburg researchers said the problem is common, and affects about one in 10 pregnancies. Their research showed women affected are more likely to experience a long labour, and need an assisted delivery.
They called for a blood test for it to become a routine part of the antenatal check.
Professor Victor Pop, who led the research, said: “Recent findings have shown that motor development in children at the age of two is related to low levels of thyroid hormone in pregnancy.
“It follows that impaired maternal thyroid function could also influence foetal movement,” he said.