Calcium supplementation, exercise, dietary therapy, the use of prescription ……, as children grow older, see their own children are still shorter than their peers a large cut, many parents will be more and more anxious, so exhaust all kinds of ways to help children’s height “leap up”. However, clinical investigation found that there are still many young children’s height does not follow the people. In fact, many children are born with short stature, which is called ‘small for gestational age’, and if not detected and treated early, it may affect the child’s lifelong height. Therefore, parents of “less than fetal age children” should pay special attention to their children’s height development, abandoning the fluke mentality of “children develop late and can still grow when they reach puberty”, and bring their children to the doctor as soon as they find that their height growth is slow. The company’s main business is to provide a wide range of products and services to its customers. It turns out that although Sweetie was born at full term, she was thinner than other newborns from the moment she was born, weighing only 4.5 pounds and measuring about 42 centimeters in length. For this reason, Sweetie had to live in a warm box for half a month before returning to her parents. Although the skinny Sweetie’s body is weaker than other children, but under the careful care of mom and dad, finally grew up peacefully, the only shortcoming is that the little girl has always been shorter than children of the same age a large cut. I originally thought that the child a little older will “see the wind grow”, but who knows the child is now in the fourth grade, but always shorter than children of the same age a lot. Sweet mother began to be anxious: “Her father and I are not short, how can she be so small?” She is so small. After hearing from a colleague that a child’s short stature can grow taller after treatment, Sweetie’s mom was so blessed that she rushed to bring her child to seek medical help. The doctor did a detailed examination of Sweetie, and combined with Sweetie’s mother’s description of her daughter’s growth, determined that the root of Sweetie’s failure to grow was laid in the mother’s womb, and that the child was born a “less than fetal age child” due to poor intrauterine development. According to the mother’s recollection, Sugar has always been a lot shorter than children of the same age since birth, and it seems that she has not seen her grow much taller in a short period of time. This means that Sweetie did not have the growth catch-up that most “less than gestational age children” have between birth and 2 years of age. The doctor told Sweetie’s mother that if she had been treated earlier, she might not be worried about her height, but now that she is 10 years old, the effect of treatment will be compromised. The “less than gestational age child” is a child who is obviously born at full term, but whose height and weight at birth are lower than the standard, and whose birth weight is more than 2500g. Although the concept of “less than gestational age” has been revised to mean that birth weight and/or length is below the 3rd percentile of normal values or 2 standard deviations below the normal mean for the same gestational age, the majority still use the previous criteria, i.e., birth weight is below the 10th percentile of normal values or 2 standard deviations below the normal mean for the same gestational age. The majority of these criteria are still used, i.e., the 10th percentile birth weight or 2 standard deviations below the normal mean for the same gestational age. The incidence of “less than gestational age” is reported to be 5% abroad and 5%-15% in China. After the birth of “less than gestational age” babies, such as proper feeding, no or less sick, regular life, happy spirit, many children will begin to appear two months after birth growth catch-up, to 6 months of growth catch-up is the most obvious, can catch up with the normal height of children accounted for 85% to 90%, to 2 years old most of them can catch up with the normal child By 2 years of age, most of them can catch up with the normal height of children. However, 10%-15% of children still cannot catch up after 2-3 years of age, and these children may not be able to catch up with other children of the same age in their lifetime. Most of these children will still be below the average height of normal children minus 2 standard deviations when they reach adulthood, which means they are short. According to statistics, about 20% of short stature in adults is caused by “small for gestational age”, and because of the high incidence of “small for gestational age”, “small for gestational age” has become a major cause of short stature in children and adolescents. The incidence of “small for gestational age” has become an important cause of short stature in children and adolescents in China. In recent years, scholars have paid great attention to the postnatal growth delay of “small for gestational age” children. If a child is born as a “small for gestational age child”, parents should pay special attention to the change of their child’s height. It is important to know that the height growth of “less than fetal age children” from birth to two years old is like a sprint race, and the standard height at two years old is the “passing line”. To catch up with this line means that the child has passed this hurdle, the ability to grow without problems, and vice versa means that the child may have growth disorders. Generally at the age of 2 years old, “less than fetal age children” who are not able to catch up adequately, if not treated, the gap between their height and that of their peers will likely grow larger and larger, while “less than fetal age children” who are still not growing to catch up at the age of 3 years old will find it difficult to catch up again. So, what causes a small number of younger-than-gestational-age children to fail to grow sufficiently after birth? Although the reasons for this are not clear, studies have found that 50% to 60% of prepubertal small for gestational age children have abnormal growth hormone secretion or an abnormal response to the arginine stimulation test and a significant decrease in insulin-like growth factor-1 in the blood. In some children younger than gestational age, although growth hormone secretion is normal, the sensitivity of tissues to growth hormone is reduced, which may be due to abnormal growth hormone receptor genes. In addition, “small for gestational age” children who do not appear to catch up clinically are more likely to be severely preterm and have severe growth retardation. Numerous studies have shown that the younger the age at which treatment for short stature begins, the shorter the height, the lighter the body mass, and the greater the ultimate height gain. In July 2001, the FDA approved the use of recombinant growth hormone for the long-term treatment of “small for gestational age” children who do not show catch-up growth at age 2. The goal is to induce growth catch-up in early childhood, maintain normal growth in late childhood, and increase height in adulthood to normal adult height levels. Growth hormone treatment for children younger than fetal age has been widely used and has achieved more satisfactory results. According to the current height standard for 2-year-old children in China, the average height for boys is 88.5 cm and for girls is 87.2 cm. If a child is born at full term weighing less than 2.5 kg, and at the age of two the height of a boy is less than 81.6 cm and that of a girl is less than 80.5 cm, parents should take the child to the doctor as soon as possible and start treatment as soon as the diagnosis is confirmed.