Women have babies because that's the way to keep the world populated.
With laboratory methods now being tested, having babies may one day become unnecessary. For hundreds of years of recorded history, babies have been born without any great regard for whether they were wanted, tolerated or unwelcomed. Desired babies fared well enough most of the time. A woman is not necessarily a saint because she has a child. The woman who can hardly wait for her baby to be born may find all her maternalism was expended in the waiting.