Chinese children’s height comparison table Will children’s height be higher if their parents are taller? If children grow taller later, will they grow taller than others?
Parents are very concerned about the height of their children. Dr. Tang Shujing, chief physician of pediatrics at the Third People’s Hospital of Xiaoshan District, has been following more than 7,000 children in 10 primary and secondary schools in Xiaoshan for more than ten years. Recently, the results of the survey were published, answering each of these two questions.
The 17-year-old girl is 132 cm tall Halfway through the summer vacation, Director Tang’s clinic is still very busy. Yesterday, she just received some parents of short children, including a girl who came from Henan.
“It’s a pity for this girl, if she had come earlier, she might not have had such a result.” Director Tang said the family thought the child was a late bloomer and had not been particularly concerned about her height. It was only when she was 17 years old, not only was she short, but her breasts had not developed either, that she realized the situation was not right.
The examination found that the girl was only 132 cm tall, without a uterus and ovaries, because of the lack of sex hormones, resulting in the inability to grow, and no way to have children in the future. “If she had come earlier, she could still grow taller and develop secondary sexual characteristics through artificial hormone replacement, etc. Although also unable to have children, she can get married and live a normal life.” Director Tang said.
The more children Director Tang encounters who come to the clinic are high school students preparing for alarm school or military school, hoping to take advantage of summer treatment to increase their height a bit.
“The parents who come in say that a centimeter of growth is all that is needed. But I can only regret to say that it comes too late, the development has been completed, there is no way to grow taller.” Director Tang said.
The parents of these children, all believers in the folk theory of late growth, believe that the reason their children are shorter than other children is because they develop later and will catch up or even surpass other children later.
Is this really the case? Director Tang, in order to give parents a sober understanding of late growth, has been working with colleagues since 1997 to conduct height tracking surveys on children in 10 primary and secondary schools in Xiaoshan.
“Genetic target height, is based on the influence of hereditary parental height on the child’s height. Usually, if the parents are tall, the child is also tall.” Director Tang provided a formula for calculating genetic target height.
If it is a boy, the genetic target height is equal to the sum of the parents’ heights (in centimeters) divided by 2, then add 6.5 centimeters. In the case of a girl, the genetic target height is equal to the sum of the parents’ heights divided by 2, and then subtracted by 6.5 cm.
For example, if the father is 180 cm tall and the mother is 172 cm tall, the genetic target height of the son is about 182.5 cm, and the genetic target height of the daughter is about 169.5 cm.
Three types of children should be screened in time. “Parental height is not an absolute influencing factor. 21 children with idiopathic short stature, a significant number of children have parents whose height is above the average height of the population, and there is no definite reason as to why they are short. For these children, a growth hormone treatment can be taken.” Director Tang said.
Regardless of the cause of short children, the key is to detect it early.
Director Tang recommends three types of children for early height screening. One category is children who are born shorter than other children, the second is preschoolers who are one head shorter than their peers, and the third is children who always sit in the first row after school.
For these three types of children, an ultrasound screening and bone age check can be done at a hospital specialist to rule out various disease factors.
Ninety percent of the children were diseased short. From September 1997, Director Tang and her colleagues monitored the height of 7,444 children with normal height in 10 primary and secondary schools in three towns and one township in Xiaoshan, with students ranging in age from 6 to 15 years old. Among the 7444 cases, 52 cases were found to be short in stature.
Subsequently, these 52 cases were followed up. By December 2010, a total of 41 cases were followed up, including 24 males and 17 females. Only four cases were found to have physical delay in puberty, which is known as “late growth”.
“During the follow-up, we found that most of the parents of these 41 cases thought their children were late growing and would grow taller in the future, but in fact, only 4 cases or 9.8% of them were really late growing, and more than 90% of them were diseased short.” Director Tang said with regret.
From a medical point of view, late growth is actually delayed puberty, which generally starts at the age of 10-11 for girls and 12-13 for boys. Some children, however, have a delayed start of one to two years because of their late development, which gives some uninformed people the misconception that children who are shorter than their peers are late growers.
Of the 37 cases of children with disease dwarfism, two were partial growth hormone deficient, one was hypothyroid, four were younger than fetal age, nine were nutritional dwarfism, and 21 were idiopathic dwarfism.
“From these types of classifications, you will see that there are very many factors that affect height, some of which are easy to detect and some of which are not.” Director Tang said that nutritional dwarfism is easier for parents to detect, as these children are relatively thin and small, while hypothyroidism and sex hormone and growth hormone deficiency are not as easy to detect.
After dietary adjustment, supplementation of trace elements and administration of thyroxine tablets and other etiological treatments for children with nutritional dwarfism and hypothyroidism, the final adult height can approach or reach the range of genetic target height.
Children can do more stretching exercises to grow taller “Excluding factors such as diseases, children’s growth is mainly determined by four types of factors, parents can pay more attention from these aspects.” Director Tang introduced.
First is nutrition, nowadays children are generally better nutrition, the previous children are under-nutrition, now children are over-nutrition, do not give children excessive supplements to avoid early development.
Secondly, sleep, preschool children need at least 9 hours of sleep, the 9 hours refers to the sleep time at night, because children’s growth hormone is secreted during the deep sleep at night. Now many parents because of their own night life is rich, but also delay the child’s sleep to late at night, and then get up very late in the morning, although there are also 9 hours, but not as good as the early to bed children.
The third is to have more exercise. Director Tang suggested that parents can let their children do more vertical stretching exercises, such as swimming and touching high exercise.
Finally, it is not to give children too much psychological pressure. During the survey of various schools, Director Tang once compared the height of children in two schools in the same city and found that the average height of children in the city center school was slightly lower than that in the suburbs; further investigation found that children in the city were too burdened with schoolwork, lacked outdoor activities and had more mental stress, which inhibited the pituitary gland from secreting growth hormone.