The role of a wife has changed significantly during the last hundred years.
Woman now have more freedom than ever before to choose her role to her husband.
Many woman may decide to invest heavily in a career and push off childbearing until a later age. Other woman decide that they want to be a wife in the traditional sense.
Husbands and wives can make all kinds of arrangements that are perfectly workable between each other.
It is important that both parties are aware of the expectations that the other are bringing into the marriage so that there isn't friction later on.