Children's growth and development standards

For adolescents and children, it can be said that the growth and development standards at each stage are different. Because our bodies undergo rapid changes almost every day from infancy to adolescence, our height, weight, and even chest circumference will be different at each stage. So what are the growth and development standards for children? Are there any specific standard values?

Experts tell us that since everyone's physique and physical fitness are different, generally speaking, there are certain differences in height, weight and other values ​​at each stage, but the standard data for growth and development are relatively accurate to a certain extent. So what are the growth and development standards for children?

Children's growth and development standards

Growth and development is a physiological phenomenon unique to infancy and adolescence. However, growth and development is not a simple process of the body growing from small to large, but a very complex phenomenon. It involves the increase and differentiation of individual cells, and the improvement of organ structure and function. The general characteristics of children's growth and development are: height and weight increase rapidly in the first two years after birth, increase relatively steadily from the age of two to before puberty, grow rapidly during puberty, and then gradually stop. Physical development follows a head-to-tail pattern, that is, the head develops first in infancy, and as age increases, the head grows little while the limbs and trunk grow faster. In infancy, the head height accounts for 1/4 of the body, while in adults, the head height accounts for 1/8 of the body height.

Commonly used children's growth and development indicators include: weight, height, head circumference, and chest circumference.

1. Weight Weight is the most important and sensitive indicator of children's growth and development. Because weight reflects children's nutritional status, especially their recent nutritional status. Weight can be affected by many factors such as nutrition, complementary food addition, disease, etc. Weight gains fastest in the first three months after birth, generally at 600 to 1000 grams per month, and preferably not less than 600 grams. 3 to 6 months is the second fastest, with an average monthly increase of 600 to 800 grams. From 6 to 12 months, the average monthly increase is 300 grams. The growth rate of children slows down significantly after one year old, and the average weight gain of children aged 1 to 3 years is 150 grams per month. The weight of children after 1 year old can be calculated using the following formula: Weight (kg) = Age (years) + 7 (or 8)

2. Height Height is also an important indicator of children's growth and development, but it reflects the long-term nutritional status. Factors that affect growth and development in the short term (nutrition, disease, etc.) do not have a significant effect on height. It is mainly affected by genetics, race and environment. Like weight, height increases fastest in the first year after birth, with an average annual increase of 25 cm. The average growth in the second year is 10 cm, and the average growth in the third year is 4 to 7.5 cm. The body shape of children in early childhood changes from the plump type of infancy to the slender type. During this period, the trunk is slightly longer and the lower limbs are slightly shorter. After early childhood, the growth of the limbs gradually becomes faster than that of the trunk. The formula for average height after one year old is: height (cm) = age (years) + 80 (cm). Children's height and weight can be evaluated using the standards of the World Health Organization.

3. Head circumference Head circumference is an important indicator reflecting children's brain development. Head circumference increases fastest in the first year after birth. The average head circumference at birth is 34cm; at 1 year old, it is 46cm; it increases by 2cm in the second year and 1-2cm in the third year. The average head circumference at the age of 3 is 48cm, which is not much different from that of adults. From this we can see that brain development mainly occurs in the first three years after birth. In normal children, the posterior fontanelle closes at 3 months, and the anterior fontanelle closes at 1 to 1.5 years old. If closure is too late, the possibility of rickets should be considered. Some children are born with a smaller fontanelle, which closes earlier. This is related to the mother's better nutritional status during pregnancy. Therefore, we need to look at this issue comprehensively. If you do not overdose on cod liver oil or overdose or inject vitamin D, there is generally no major problem. It should be noted that it is not as people imagine: the bigger the child's head, the smarter he is. Intelligence is not directly proportional to the size of the head circumference. It is sufficient for children's head circumference to be within the normal range. If the head circumference is too large, you should consider the possibility of a brain tumor or hydrocephalus.

4. Chest circumference: When a child is born, his chest circumference is smaller than his head circumference. As the child grows older, his chest circumference gradually catches up with his head circumference. Generally, when a child is 1 year old, the chest circumference is equal to the head circumference. But now, due to the generally better nutritional status, many babies' chest circumference catches up with their head circumference before they are one year old. Factors that affect chest circumference growth include poor nutritional status, lack of physical activity and diseases causing chest deformities, such as pigeon chest, funnel chest, etc. After a child is one year old, his chest circumference grows significantly faster than his head circumference, and the chest circumference gradually exceeds the head circumference. During puberty, the chest cavity develops rapidly and transforms into an adult body shape.

Parents already have some understanding of the children's growth and development standards. In fact, if you want to judge whether your child is developing normally, you should use height, weight, head circumference and chest circumference as standards. Generally speaking, weight and height are the most obvious ways to find out whether the child's body is healthy and normal. In addition, head circumference and chest circumference will also increase with age. In short, you may as well refer to the standards introduced above to judge your child!