Fluoride exposure during pregnancy from a community water supply is associated with executive function in preschool children: A prospective ecological cohort study.

Background: On May 19, 2011, Calgary, Canada stopped fluoridating its drinking water. This prospective ecological study examined if maternal exposure to fluoride during pregnancy from drinking water that was fluoridated at the recommended level of 0.7 mg/L was associated with children's intelligence and executive function at 3-5 years of age.