10 months baby sleeps on his back, may be physiological reasons, such as sleep habits, etc., may also be pathological reasons, such as bloating, rhinitis, etc. caused by, should be timely consultation to identify the cause. 1. Physiological reasons: babies sleep on their stomachs are more secure for babies. Usually when the baby is in the mother’s body, also lying in the mother’s body, the baby is more familiar with this position, more secure, all part of the baby like to sleep on their backs. 2. Pathological reasons: (1) bloating: the baby’s digestive tract is in development, if the diet is not appropriate, eat in too much gas or the abdomen is cold, inflammation, etc., may cause symptoms of abdominal distension, the baby sleeps on his stomach, will make the abdominal distension partially relieved. (2) rhinitis: rhinitis will cause the baby to appear nasal congestion, nose, runny nose and other symptoms, the baby sleeps on his stomach can relieve the local symptoms. If you exclude physiological reasons, you should promptly consult a doctor to clarify the specific causes, and if necessary, the appropriate treatment.