Blame Andrew Wakefield. He was the one who convinced Jenny McCarthy. She's a useful idiot. And I do mean idiot. She wrote an article that's been scrubbed from the internet about how her child was an 'indigo,' meaning he would have superhuman powers. This was before his autism diagnosis, which apparently changed her mind, because that's when the article got scrubbed.
It also contained a sentence that said (paraphrased): "After my son was born, I quit smoking."