Sorry, I've got to ask it, but how is being put on their back any more of a naturally applied position than being put on their tummy? Babies lie on their back because we put them there as much as they would lie on the tummy by us putting them there...
That's what I was thinking too?? Actually, I'd think they'd prefer to be on their tummy where they can be all curled up like in the womb iykwim.