My major gripe with this sign is not the subject matter, but the language used in it. We all agreed on a language, and if you're not going to use it correctly, don't say anything at all.
How can you be pre-born? It's a lot like George Carlin's famous joke about preboarding an airplane: How can you get on an airplane before you get on the airplane? There's getting on or there isn't. There's being born and there is not being born. Two very distinctive states of being. You can be unborn or you can be born. There's no being born before you're born.
Photo credit to Space Monkey.