Because of past women's social role is not.And people have not yet been accepted.And the duties of women past child care is working at home or work, without being.
For the past women were social role and are not people accept and duties of women in the past. Is to take care of household chores or work that is not used.
Because the woman is not the social role, and yet not people accept and function of women in the past is to take care of the baby, do the housework. Work or not by force.