Or going outside the law.
THAT is my point.
Shooting an intruder IS killing a human. In such a situation, the intruder's right to life collides with the intrudee's right to life and/or property, and the law states (depending on the specific law in that area, and the circumstances of the shooting), the one intruded upon is in the right.
In much the same way, (IMO) an abortion takes place when the future human's right to life (yes, I'm assigning a right to life to the ZEF, or whatever you call it) collides with the potential mother's right to choose (and possibly, right to life, depending on the case) - and the law has determined that the right to choose is paramount.
And it would have to be a choice - the only choice removed would be killing the potential human (as I prefer to refer to the fetus/ZEF/whatever). The woman could choose to carry the child naturally, of course.