Women’s responsibilities outside of work — mainly looking after children, but also caring for sick and elderly family members — often keep them from taking on the kinds of jobs that would finally close the distance in pay between the genders.
The Real Reason Women Still Make Less Than Men
The Huffington Post

Woah there — why are you just assuming that “looking after children [and] caring for sick and elderly family members” are “women’s responsibilities”? Saying this is a problem with “life” just blithely endorses this division of labor. And saying that this reality is somehow an alternative explanation to sexism is just disingenuous. Letting these care-taking tasks fall to women is sexism.