This is one issue where I think people argue around the edges. I will say that I believe the only correct answers are always and never. The middle ground is all equivocation and red-herrings.
The bottom line is that either a fetus IS a human life deserving of the basic human rights or it is not. If the answer to this is the affirmative then abortion for any reason (to me) is immoral. On the contrary, if it is just a cluster of cells like a kidney and not a human deserving of such rights, then why should the Government be involved at all in a medical procedure?
The trouble is that whether the fetus=human or not is very subjective and philosophical, but without such an answer the rest of the debate is meaningless.