I remember reading something by that famously spiritual sage Dan
Savage about abortion.  He was reporting an argument he had with
another guy about abortion, with Savage taking the position that if a woman hadn’t gotten around to having an abortion by the time she was in her third trimester then she should go ahead with the
birth.   

It struck me at the time that this famously
liberal, gay sex columnist was taking the stance that as the fetus progressed
it became more deserving in rights, and at the time I chocked it up to his
Catholic upbringing.  But now it
makes more sense to me.  As a fetus progresses from a potential life to a viable life, the rights
of the mother to terminate that life should, in my opinion, decrease.  This idea was reinforced after reading Steve Waldman’s seminal piece called Safe,
Legal & Early – A New Way of the Thinking About Abortion.   

He writes:

This belief that life within the womb is on a continuum is
not explicitly reflected in the political debates about abortion. We debate
whether we should have parental notification–not when we should have it. We
question politicians on whether they’d provide government funding for abortion,
not ever asking whether subsidies should be provided for early abortions but
not late.

And Waldman suggests this way forward on the abortion
debate:

My fantasy is that if the political system embraced the safe-legal-early
doctrine, a few activists might even accept the legitimacy of part of their
opponents’ argument. Pro-choicers who accepted this framework would be
implicitly conceding that, for at least part of the pregnancy, there’s a
“baby” in the womb–and the woman’s right to terminate that life is
neither absolute nor nine months in duration. With early abortions not only
legal but easier, pro-choice activists could then have the confidence to accept
what many of them have publicly avoided but privately wanted: reasonable,
tightly written prohibitions on third trimester abortions while genuinely
protecting the life of the mother.

Open minded pro-lifers would take note of these concessions
from their “enemies,” viewing them as a sign that these pro-choicers–far
from being hideous baby killers–fully embrace a moral dimension to the
abortion decision.

Meanwhile, any pro-lifers who accept this framework would be
making a concession, too. They’d be saying, in effect, that if the other side
can concede that something precious is alive – and becoming more alive with
each day – then they could, in turn, acknowledge that reasonable people, of
different faiths, can disagree about when exactly that baby becomes alive
enough to have legal rights.