Compromise?

Freddie DeBoer and John Schwenkler have been debating whether pro-choicers or pro-lifers are more to blame for the abortion stalemate. Here's Freddie: 

To me, the question about abortion (and it is a philosophical and moral question, not a scientific one) is whether or not a fetus is a human, and thus deserving of human rights. If the answer is yes, I could never in good conscience support abortion, outside of specific circumstances when carrying the child to term poses significant risk of killing the mother. Not even in cases of rape or incest.

I remain a staunch supporter of abortion rights, however, because I don't believe a fetus is human. I can imagine, however, a compromise position from someone who doesn't believe that a fetus is human; it seems to me much easier for someone who believes that to compromise in the direction of more limitations on abortion, than for someone who believes that a fetus is human to compromise on more permissiveness regarding abortion. I'm just profoundly unmoved by pro-choice arguments that assert the human-ness of the fetus. So it just seems to me that there is greater moral and rhetorical space for the pro-choice side to compromise given our stance on the fundamental question.