This is best explained by the perennial problem of child care, which lifts women out of their jobs at precisely the moment their male colleagues are putting in more hours and being promoted. When researchers Mary Ann Mason, Nicholas Wolfinger, and Marc Goulden published a book on this subject in 2013, titled Do Babies Matter: Gender and Family in the Ivory Tower, they found that married mothers of young children in the United States were a third less likely to receive tenure-track jobs than married fathers of young children.
