The criteria for raising the head at 3 months of age are that the baby is lying prone on the bed, supported by the elbows, with the chest off the bed, with the head raised at 45°, with the head stabilized in the vertical hold, with the head and trunk basically in a straight line in the supine position when the head and trunk are pulled and seated, and with the lower jaw close to the chest. If the above criteria cannot be met at 3 months of age, consider motor developmental delay as well as brain injury lesions, and then combine with whether the baby has high risk factors such as preterm birth and cerebral hypoxic-ischemic lesions during the perinatal period. If the above manifestations and medical history are present, it is important to go to the hospital in time to give the necessary early intervention.