How early can we start tummy time?
Tummy time is something you can introduce your baby to as soon as you head home from the hospital. In fact, giving babies plenty of time on their tummies is not only helpful in preventing the back of a baby's skull from becoming flattened (a condition known as plagiocephaly, but it's also very good for babies' development. You simply need to be aware of two simple yet important tummy-time guidelines.
The first is that tummy time should be limited to times when your baby is awake. This is because the current (and longstanding) recommendation of the American Academy of Pediatrics is that babies should sleep on their backs in order to reduce the risk of sudden infant death syndrome (SIDS).
The other thing to keep in mind is that newborns and young babies do not have strong head, neck or chest muscles and therefore can't reliably lift up their heads and/or effectively move things away from their nose or mouth. While tummy time helps young babies build up strength in these muscles, it will be solely up to you (and any other of your baby's caregivers) to make very sure that the area where you want to lay your baby down on her tummy is clear of anything that might block her nose or mouth and interfere with her breathing. In particular, this means making sure your baby's designated tummy time area(s) do not include soft surfaces or any soft, fluffy blankets and/or stuffed animals.
Once you take into account that tummy time should be reserved for times when your baby is awake and you've got a clean, clear and safe area to lay your baby on, then there really are no real limits to tummy time. That said, some babies take to it better than others—with some laying peacefully on their bellies and contentedly attempting on occasion to practice lifting up and turning their heads, while other squawk and put up a fuss. I often find that the earlier you introduce a baby to tummy time, the more accustomed they become to it and the less fuss they make. Feel free to read my additional tips and tricks for tending to tummy time troubles.