Actually there are quite a few arguments from many people, depending on definition. If you believe that being living human biological tissue constitutes a being, then OK. If You believe some level of consciousness or experiential factor is required, then not so much.
Yes, and let's try some examples (that even include "consent"):
Example 1: the sun worshipper who forgets the UPF cream, ad subsequently develops a melanoma. That melanoma is unquestionably human tissue, and it arose because at least one party (the one who got the melanoma), obviously consented (though the sun cannot be said to have done likewise). Can it be ethical to remove that very human tissue then, just because the tanned host doesn't want it anymore, even though he knew it was a very real possibility?
Or how about the colon cancer, brought about from too much nitrites from hot dogs and bacon (big favourites)? Same deal, eh?
I am, of course, being quite facetious here. But I think we need to be very clear about something. Whatever we think we know, (many of us as older adults, which I certainly am, and some that oppose abortion here certainly seem to be), I do not believe we can discount the many ways in which younger people, or people who have been left with a certain ignorance about human sexuality (as is very often the case in the US these days), truly believe "it won't happen." And the same may be said of those who dutifully try following the "rhythm method," which we should all know is not at all foolproof.
We call the lapses by many names: errors, misjudgments, mistakes, lapses, submission to stronger impulses...
I continuously wait for contributors like
@dianaiad to make allowances for such eventualities, but they don't seem able to go there.