Women with moderate to severe iodine deficiency may have a more difficult time conceiving, suggests an observational study by researchers from the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD).
Iodine deficiency is common in the US population and in pregnant women specifically. The study included 467 women who were trying to become pregnant between 2005 and 2009. It found that 44.3% had urine iodine-creatine ratios of less than 50 μg/g. Compared with women with normal iodine levels or mild iodine deficiency, women with iodine-creatine ratios lower than 50 μg/g had a 46% lower chance of becoming pregnant in any menstrual cycle. Women with milder iodine deficiencies of between 50 and 99 μg/g also took longer to conceive than women with sufficient iodine levels, but the difference wasn’t statistically significant.