It depends on the relationship between the couples and it also depends upon their culture. In olden times in India, the men were considered the head of household, and the women took care of the home and the children. However, as India has become somewhat more Westernized, women are working as well as the men.
In the US, it really depends on the relationship of the couple. If the husband/boyfriend is not working, usually he takes care of the kids or at least helps out with housework around the house and vice versa with the women. However, there are men who expect their wives/girlfriends to take care of everything even though the women work to provide income for the family.
That is a great question.