Infants can sleep on their backs, but always under parental supervision.
For infants supine position, moderate side lying and sleeping on their backs are all fine. It’s impossible to talk about which is better or worse for the child. Sleeping on the stomach reduces the infant’s early startle reflex, so it somehow has a sleep-enhancing effect, as well as improving the shape of the head.
However, parents should pay special attention to the fact that if the child sleeps on his or her stomach, a soft bed should not be used so that the head does not sink into the bedding. At the same time, the bed and the surrounding do not put particularly soft cloth plush toys, etc., which is easy to increase the risk of choking children, so when sleeping on their stomachs, parents need to watch over the side, especially for the baby can not be stabilized to raise their heads.
It is best not to use the same sleeping position for a long time.