I guess you have never heard of DNA testing (or seen the Maury Povich show)? Incest can be 100% proven or disproven be simple tests.
To get an abortion under a rape exception, a woman would have to file a police report and have a rape kit done.
You seem to be looking for any exuse to get conservatives to surrender to the pro-death agenada. If we do that, we might as well just become Democrats.
You may have the last word.