The growing body of research about the causes of autism continues to point toward pregnancy and delivery as moments when the brain changes associated with the disorder can occur. Earlier this week, a study was published in the Journal of the American Medical Association, reporting that inducing labor may raise the risk of autism because babies likely to develop autism may fail to send out the biochemical signals to initiate labor. USA Today has more on a second study, which associates an elevated autism risk with an untreated thyroid condition in pregnant women:
One study, published Tuesday in Annals of Neurology, finds a four-fold increase in autism among women who had very low levels of a key thyroid hormone, called thyroxine. Researchers found the link in a study of more than 4,000 Dutch mothers and children. Doctors took blood samples from women around the 13th week of pregnancy, then followed up six years later, asking women to fill out a standard psychological checklist about the child's behavior and emotional traits.