Her body isn't being hacked to pieces or burned in chemicals. It's that of the unborn child. If she didn't want it there, she shouldn't have willingly participated in the process that makes babies.
Okay. Let's take your argument and run with it. First of all, your argument allows an abortion in the case of rape, since the woman did not
willingly participate in the process that causes pregnancy. Secondly, what if the pregnancy is accidental? What if the man agreed to pull out, or what if he wore a condom, or what if she was on the pill, etc.? In that case, is an abortion allowed, OR is any woman engaging in sex necessarily give up her rights to her body for the next nine months?