Baby stretching is often caused by normal physiological reasons, intestinal flatulence and brain injury. 1. Physiological reasons: if the baby is not enough sleep, neurodevelopment is not perfect, may observe that the baby loves to stretch, not combined with other symptoms, strengthen the rest can be restored to normal, no need for special intervention. 2. Intestinal flatulence: Low-month-old babies with abdominal distension, intestinal flatulence, may be manifested as legs stirrups straight, accompanied by breathlessness, crying, often occurring in the birth of 3 weeks to 3-month-old babies, parents can strengthen the soothing, massage the abdomen to help exhaust. 3. Brain injury: the baby shows symptoms of high muscle tone, such as leaning back and jerking, and often continues in this position, which requires timely medical assessment of whether the brain injury. Baby old stretching, 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.