Numerous scientific studies have examined the effect of maternal work on children's behavior and academic performance; others have looked at its effect on their physical and emotional health. The results of these studies have been inconsistent. Searching for more definitive answers, researchers at UC Irvine combined the results of 69 different studies on the topic. Their findings, published by the American Psychological Assn. in 2010, were reassuring. With few exceptions, children whose mothers returned to work when they were young fared just as well as those with stay-at-home moms. "The only negative effects were found with very intensive, full-time employment early on," says Wendy Goldberg, Professor, Psychology and Social Behavior. "We have to look at other factors that affect child achievement and behavior. Maternal work isn't the whole story by any means."