My wife caught me having sex with my daughter I don't know what surprised her more, that or the fact the hospital gave me the fetus
I'm disturbed by your comment. Is this something you have done or did you hear someone say this?
It's just a joke I read somewhere. I'm not into incest, don't worry.
Making jokes about incest is inappropriate. If you tell these kind of jokes to people, they will likely believe that you are into and okay with incest. This will damage your character and reputation.