No, I never said that. Abortion is always immoral, even in the case that the woman was coerced to have sex. However, if she was coerced, there are two immoral choices: either we allow the woman to abort, which is immoral, or we prohibit her from aborting, which is also immoral (because she never consented to have sex and get pregnant).
So, no, morality does not change according to circumstances. It is always immoral to abort a child, and it is always immoral to force someone to go through unwanted suffering which was not consented. In most abortions, since the woman has already consented to have sex and, consequently, possibly get pregnant, the second parameter does not apply and the best choice is clear. However, if the woman has been raped, it is still immoral to do both things.
In other words, as I have said earlier, every foetus has the right to live and every woman has the right to choose whether to get pregnant. If the woman has already used her right, that right is not given back to her; but, if she has not (as it happens in a situation of rape), she still has the right to choose, and it is immoral to take it away from her.