Iodine deficiency during pregnancy

Iodine is an important part of our diet, and many women don’t get enough of it during pregnancy. Our researchers have been finding out how common iodine deficiency is among obese pregnant women in the UK and whether it is linked to pregnancy complications.
  • Author's list

    Dr Angela Flynn, Dr Sara White, Professor Lucilla Poston, Dr Carolyn Gill, Anna Brockbank, Dr Kathryn Dalrymple

    Start date: 2019
    End date: 2020

  • Research centre

  • Research status

    Completed projects

Why do we need this research?

Iodine is an important nutrient that pregnant women need to help their babies’ brains develop properly. Low iodine levels during pregnancy can lead to problems for the child later in life, such as difficulty with speech and reading. Iodine deficiency can also lead to health problems for women.

There’s some evidence that many pregnant women don’t get enough iodine in their diet during pregnancy. However, we don’t know the true extent of iodine deficiency among pregnant women, and how the levels of iodine in mothers’ bodies might change during pregnancy.

What’s happened in this project?

Researchers funded by Tommy’s looked at data from a study called UPBEAT, which involved more than 1,500 pregnant women with obesity, to find out more about iodine deficiency during pregnancy. These women donated blood and urine samples throughout their pregnancy. By looking at nearly 1,000 urine samples donated early in the second trimester of pregnancy (15–18 weeks), our researchers found that 70% of the obese women in this study were iodine deficient. They also found that the women who had lower levels of iodine in their urine were more likely to have babies with a lower birthweight.

What difference will this project make?

This study has provided a detailed picture of iodine deficiency in obese pregnant women and has shown that it is linked to lower birthweight. The findings from this research could strengthen recommendations for pregnant women to ensure they get enough iodine in their diet or could lead to trials of iodine supplements during pregnancy.

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