The woman purposely availed herself to that position, the baby did not.
Doesn't matter, its still ultimately in her body. What if she decides to take up smoking and drinking? Are you going to force her to also make sure the baby is healthy?
It's not a crime to drink and/or smoke while pregnant, but I wouldn't be opposed to it. Again, she purposely availed herself to the situation, it's her obligation to behave responsibly. These are the consequences of her actions.
I don't think she's obligated to do anything. The only consequence is she now has a choice, keep it or abort it.