To determine the life expectancy of preterm infants when they grow up, it is mainly based on the specific situation targeted analysis. First of all, the life expectancy of preterm babies when they grow up is the same as that of children of the same age. Premature babies are only born earlier, the other development of newborns is normal, there is no brain hypoxia, and the child’s growth and development will get a significant catch-up. Before the child is one year old, it can often catch up with children of the same age, and the child’s body is also very healthy, and the life expectancy is the same as that of normal children of the same age. Secondly, there is the case of shorter life expectancy. If a premature child has serious complications, such as severe brain defects or the presence of pulmonary dysplasia, as well as combined congenital heart disease, the child’s life expectancy is somewhat shorter than that of children of the same age.