The height and weight of preterm babies refer to the standard for full-term babies. 15-month-old male babies have a normal height of 76.9~82.8cm and a normal weight of 9.57~11.93kg, while 15-month-old female babies have a normal height of 75.6~81.4cm and a normal weight of 9.01~11.08kg. The World Health Organization refers to newborns with a gestational age of less than 37 weeks but greater than 28 weeks and a birth weight of less than 2,500g as preterm babies. Children’s height and weight are within one standard deviation above and below the median for children of the same age, which is a normal level of development. The median height of 15-month-old male babies is 79.8cm, and the median weight of 15-month-old male babies is 10.68kg. After one standard deviation up and down, the height is 76.9~82.8cm, and the weight is 9.57~11.93kg as normal. The median height of a 15-month-old female baby is 78.5cm, the median weight of a 15-month-old female baby is 10.02kg, and after one standard deviation up and down it is 75.6~81.4cm in height and 9.01~11.08kg in weight as normal. If you find that your child’s height and weight are abnormal, please go to a regular hospital in time to seek medical treatment and intervene under the guidance of a doctor.