People have inmune systems and take medicines, go through surgeries and basically use medicine to live longer and survive things that would have kill them otherwise.

Humans reject nature whenever is convinient and improves their life quality and survival rates. And that is OK. Abortion is a medical procedure just like any other. You might dislike it, but it is still there and helps pregnant people in situations where continue the pregancy would be bad for them. Including a high risk of death at birth.

Of course, you have the choice to reject medicine if you are ill and depend only on your inmmune system. I mean, you have a choice over your own body. XD