Back curvature of eight-month-old babies may be caused by physiological reasons such as insufficient spinal support ability, or it may be caused by congenital scoliosis, calcium deficiency and so on. 1. Physiological reasons: due to the lack of spinal support ability of the baby, the baby can not sit up straight, there can be a curved back performance, this is a normal physiological phenomenon, with the growth and development of the baby, the back curvature will be improved. 2. congenital scoliosis: babies may be due to congenital changes in spinal structure, intervertebral discs, muscles, etc. caused by spinal vertebrae rotation, resulting in congenital scoliosis, eight-month-old babies due to scoliosis can show back curvature. 3. Calcium deficiency: the baby’s bone development on the calcium demand, due to calcium intake is insufficient, can lead to the baby’s bone development is not good, the vertebrae development is not good will affect the support function, leading to the baby back curvature of the symptoms. Eight months baby back bends, there may be other reasons, timely take the baby to the hospital, improve the examination, clear cause to give targeted treatment.