You wanna talk about birth control? Hell i'm imagineing that espically during the early part of pregancy that this is not a very intrustive operation(I could be wrong here) this would make it even less painful(I bet you will find women who have refused to have an abortion based on friend's experiences, however how prevelant that is i do not know). What this could lead to is more women seeking this extraction method more than abortion was ever used.
You asked my opinion on the social cost invovled? I'm afraid to really jump into this since i haven't thought about it yet. Think of it this way though. On one side we could have continued abortion(which I think just about everyone on here agrees is wrong). On the other hand we may a crisis on our child welfare system by a huge surge of normally aborted babies and due to my point above possibly even more babies due to an increased use of the extraction method as birth control. Do I think that's acceptable social cost? I do not know. What I want to know is... who the hell is going to take care of all these kids and what price might they pay.. will we raise an extra abudance of people hating bitter kids.. or will we find some way to raise them properly?
I think that, in the end, it will come down to the question of why abortion is legal in this country. Is it legal out of respect for a woman's supposed right to not be pregnant, or is it legal because we wish to enjoy the benefits of ridding our society of those who would burden it financially and socially? I don't know why you and other pro-choicers believe abortion should be legal, but according to the Supreme Court, it is legal to serve the bodily integrity rights of the woman. A transplant procedure utilizing an artificial womb would allow a woman to exercise those rights without harming the baby. That should be the end of the debate. Whatever problems we may encounter as a result of not exterminating our children, we'll just have to deal with.