I value sentience, the lowest form of it. Therefore contraception failure plays no role in you having or not having an abortion for me. If you valued a human life from contraception, than yes 50% you could argue aren't valid abortions. I could have caused my cancer if I subjected myself to radiation knowing that I'll 30% get cancer. Or i could have caused it but count be blamed if i wore a protective suit. What's the problem with saying that you caused it? It wasn't deliberately caused, so...?

Yes, and no. I would argue that you take responsibility and go through birth. I wouldn't force anyone, but the part where you knowingly brought that life. From not sentient to sentient in your belly and didn't abort before. That should be like you forcing any other human to be dependent on you and than refusing to keep them that way. Yucky Ofc women aren't cars. Don't be silly. It's a metaphor.