Personally, I think it's wrong, except in cases where the pregnancy is really a major threat to the mother's health, like ectopic pregnancies or where the pregnancy has caused something horrendous to happen to the mother. Chances are, that the developing baby is probably dead anyways.
But, that's my personal belief and opinion. There was a time when I had a situation where I had to really wonder what I would do; I was in nursing school, living at home, and the would-be father turned out to be a complete idiot. It's a really hard thing. I was "lucky" in a sense; if I had been pregnant, I wasn't pregnant for long. I believe that I did have a miscarriage.
I don't think it's right for a woman to use abortion as birth control though, because if the procedure isn't done right, it can cause infections and scarring and possibly infertility in the future. I took care of a couple of girls and women who'd had "botched" abortions and it made them really, really sick.
Anyhoo, that's just my two cents on it.
--Heather