Women who took antidepressants in the last six months of pregnancy were 87% more likely to have a child later diagnosed with autism. Doctors saw no increase in autism rates in women who took medication for depression in the first three months of pregnancy, according to [a new] study, published online Monday in JAMA Pediatrics. In the U.S., about 2.2% of children ages 3 to 17 - about one in 45 - have autism, according to the Center for Disease Control and Prevention's National Health Interview Survey, conducted in 2014. Women who took a specific type of antidepressants, called selective serotonin re-uptake inhibitors, or SSRIs, had more than double the risk of having a child with autism. Women who took more than one medication for depression ... were four times as likely to have a child with autism. The new study is ... part of a growing body of research that suggests that the events that cause autism largely occur before birth. Studies have found that children are at higher risk for autism, for example, if they are born early or very small. Children are also at higher risk if they are in medical distress during delivery; if they have older mothers or fathers; or if they are born less than a year after an older sibling.