Well, tell me why women obtaining an abortion are not prosecuted. There must be a reason.
Is this a joke? Are you justifying abortion because women aren't prosecuted for getting one?
I don't know the laws prior to Roe v Wade, whether a woman was legally culpable or not, but if a woman wasn't prosecuted for having an abortion and legally should have been, then the obvious answer is because police and prosecutors failed to do their job.
But a failure to prosecute, as I clearly stated, is no answer as to whether or not abortion is killing. A failure to prosecute, as could easily be inferred from my previous post, is simply a cultural decision that it is killing that we allow.