Never in my life, throughout all of my pregnancies have I heard of that. Sometimes researching things on the internet is NOT a good idea becuase there is so much misinformation that it will just make you paranoid. If you are really concerned, call your ob and ask.
i highly doubt this is something to be worried about, but ask your OB just to be on the safe side... you can never ask them too many questions...i bugged the sh1t out of my ob & her nurses lol :)
I've read how the "smell" can cause irritations to a person in general (although how many people are really affected by this seems to be unclear) There's nothing concrete that shows it's dangerous though. Studies just say it might be. Honestly, I don't think you have anything to worry about with the stickers, nor with the smell in the car.
I've never heard of that but it can't hurt to ask your OB