Are the Women Who Are Accused Witches in New England the Model of Older Womanhood?

Many of the women who are accused witches in new england are grandmothers. These are women no longer looking forward to lives producers of children. But why was it that older women were more likely targets for accusations? I think part of it has to do with the fact that a woman who's born her children has sort of served her purpose in the household in a certain way.