Abortion was originally introduced and legalised (in 1967) under extreme circumstances, but the action on laws were of course loosened, and nowadays it is really easy to get an abortion.
Abortions are better than going to 'back street' doctors who would do really nasty and dangerous things to get rid of unborn children. However, the abortion law is constantly being abused, for example parents who wanted a child, conceived one and then aborted it for something 'little' and easily fixable (e.g. the whole cleft palate saga).
I'm not too keen on the idea of aborting after 24 weeks (I watched this programme where after 24 weeks they have to manually break the foetus into pieces to get it out of the uterus) but in some cases it has to be done (e.g. when the mother's life is in danger).
Personally, I agree with abortions. Women shouldn't be told what to do by societies that base their morals on religion. It's their choice.