There are many manifestations of developmental delay in babies, such as mental retardation, language retardation, motor retardation and physical retardation. 1. Mental retardation: baby developmental delay can show mental retardation, the baby’s intelligence may be lower than children of the same age. School-age children show poor academic performance. 2. Delayed language development: Some babies with developmental delay may have delayed language development, so babies may understand the meaning of each other’s language, but cannot express it in their own words, or their ability to understand language may also be limited. 3. Motor retardation: The baby may also show delayed behavior, such as not being able to hold his head up at 3 months of age and not being able to stand up at 1 year of age. 4. Delayed physical development: The height, weight, head circumference and other growth levels of babies will be lower than the lower limit of normal babies. There are many manifestations of developmental delay in babies, after the above manifestations, it is necessary to go to the hospital in a timely manner to improve the examination and take standardized treatment in accordance with the doctor’s instructions, and it is usually recommended that regular visits to the Department of Children’s Health, to follow up on the growth and development of the baby’s physical growth and development, and if there is any abnormality, it is necessary to intervene in an early stage.