At some point, be it conception or whichever trimester you choose, the fetus becomes a baby and killing it is murder. Now generally, when we're talking about killing someone, we want to err on the side of caution. The means by which one becomes pregnant are well known. So are the means to prevent pregnancy with better than 99% success. Given all this, unless a women's life is in danger,or she became pregnant via a nonconsentual sex act, abortion should not be allowed. We should err on the side of protecting life. The women made her "choice" when she decided to have sex without birth control or to run the 1% risk of getting pregnant with birth control.