6 months old baby sleeping on his back, considering physiological or pathological factors, physiological factors such as personal habits; pathological factors such as indigestion, etc., can cause babies to sleep on their backs. 1. physiological factors: some babies due to personal physical reasons, sleep on their stomachs more comfortable, and over time will develop into a personal habit, which is a normal physiological phenomenon. 2. Pathological factors: due to the special physiological structure of the baby’s stomach, sleep on the stomach to promote digestion, so there is indigestion, the baby will subconsciously sleep on the stomach to relieve indigestion brought about by the symptoms of discomfort, to ensure the quality of sleep. 6 months old baby sleep on his back, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.