In the 19th-century U.S., finding a mother of young children who worked was rare. The big exception was black mothers, many of whom were employed as domestics. That situation has changed, most likely because the economy since the early 20th century began creating an increasing number of white-collar jobs that could help support a more affluent way of life. The movement of mothers out of the home and into offices and shops happened all over the Western world, with some countries such as Austria, Belgium and the Netherlands substantially exceeding the U.S. in the proportion of mothers with very young children in the workforce.

Folk wisdom has long held that working mothers do severe harm to their children, and indeed one academic, University of Alberta chemist Gordon Freeman, claimed in a 1990 article in the Canadian Journal of Physics that they inflict "serious psychological damage" on their children, leading to teenage sex, drug use and other problems.