I just had to do a research paper on it, so I'll throw my two cents in.
Basically, I think it needs to be kept legal. Women have been having abortions all through out history, even in places where it is illegal and a severe sin. In places where it was/is illegal, it is hard and expensive for a woman to find a qualified person to perform one. This would lead most to go to someone who may not be qualified, and who's tools and methods may not be safe, causing many more deaths of the mothers.
After researching the methods of abortion, my views have changed slightly from what they used to be. While I still want it to be the woman's right to choose, I'd rather them not have an abortion, short of taking drugs (such as RU-486) at an extremely early period in their pregnancy.
People often bring up cases of rape and incest. Some women do still carry the child, however, most don't. This right here, I believe, proves that keeping abortion legal is not necessarily a bad thing, because with the woman's right to choose, it means that she can choose to have the baby, even in such "extreme" cases as these.
That's really just a short overview of what I wrote.. my whole paper was like 11 pages, and I won't bore you with that
