Lygre GB, et al. - Researchers gauged the possible associations between symptoms related to attention-deficit and hyperactivity disorder (ADHD) in children of 3 and 5 years of age and prenatal exposure to mercury from mothers’ amalgam fillings. In order to estimate the association between ADHD symptoms and prenatal exposure to amalgam fillings, they used the logistic regression models, including mothers’ age, education, body mass index, parity, smoking and alcohol consumption during pregnancy. In children prenatally exposed to mother's amalgam fillings, findings did not suggest any indication of increased risk of ADHD-related symptoms.