I have a book called "gentle mothering" and it does say about cosleeping and breastfeeding may actually be safer because they found mother's to be much more alert.
The doc said basically the same thing. That when the baby sleeps on your breast you're linked and so move together. It also said ff babies go into a deeper sleep and because not on the breast you're less aware it's there.
They also said that formula compaines influence maternity wards to discourage bf. Apparently its the formula companies that encourage babies to be kept apart from mums in America.