Women with moderate to severe iodine deficiency may take longer to achieve a pregnancy, according to a study by researchers at the National Institutes of Health. The study is the first to investigate the potential effects of mild to moderate iodine deficiency — common among women in the US and the UK — on the ability to become pregnant.

Iodine is a mineral used by the body to regulate metabolism, bone growth and brain development in children. It is found in seafood, iodized salt, dairy products, and some fruits and vegetables. Severe iodine deficiency has long been known to cause intellectual and developmental delays in infants.