Genetic height calculation method
The CMH method, in which the average parental height of 10.5 cm is the target height for boys and the average parental height of 6.5 cm is the target height for girls, has been widely used in pediatric practice. This method has been commonly used since the 1970s.
The specific formula is.
Boy = (father’s height + mother’s height + 13)/2±8 cm
Girls = (father’s height + mother’s height – 13)/2±8cm
Due to the obvious improvement in living standards in China in recent years, many of the previous generation may have not received more timely and effective treatment due to inadequate nutrition or illnesses that caused adequate height growth, and now children’s adult height is often higher than genetic height. And the CMH method takes genetic factors to 100%, which is obviously unreasonable.
At the same time, genetic height in recent years also found that there is a regression phenomenon.
That is, if both spouses are taller, the child’s genetic height will be slightly lower than the calculated height, and if both spouses are shorter, the genetic height will be slightly higher than the calculated height. Because it is more common for tall people to find tall people to marry and short people to find short people to marry, and humans do not experience a gradual increase in height differences due to this phenomenon.
Some scholars, through adequate research, proposed a new way of calculating target height, FPH (the Final Height for Parental Height) method, which has been verified in some domestic areas and proved to be more accurate and reasonable, and thus has now replaced the previously mentioned CMH method.
The formula for the FPH method is.
Boy = 45.99 + 0.78 × (father’s height + mother’s height) ÷ 2 ± 5.29cm
Girls = 37.85 + 0.75 × (father’s height + mother’s height) ÷ 2 ± 5.29cm
Here we need to remind you of the following:
1, the formula is statistically processed, only about 95% of normal people in this range, not necessarily everyone can reach;
2. The ±5.29cm behind the calculated median value is the statistical standard deviation, which may be higher or lower than the median value for normal people, but it does not mean that a completely normal person can add 5.29cm to the genetic height base through balanced nutrition, good sleep and exercise;
3, genetic height is only the range of adult height that a perfectly normal person should achieve, it does not mean that all children can achieve. Do not disregard your child’s growth and development because the calculated genetic height is still acceptable. Shortness is also a disease, and there are often children with short children whose parents are both tall, because a high parental height does not mean that the child will not have a growth hormone deficiency disease;
4. Don’t be too pessimistic if your parents are short. Familial dwarfism can be classified as idiopathic dwarfism. In most cases, as long as the epiphysis is not closed, it is possible to improve lifetime height to some extent through appropriate treatment. At the same time, because the parents have not undergone any examination and treatment for dwarfism in the past, it does not mean that there are no diseases affecting height in the family;
5, due to the improvement of living standards, food sex hormones from time to time inevitable, health care products in the sex hormone more proliferate, coupled with too much stimulation of bad information, children’s development in general early, precocious sexual maturity also increased significantly. You can’t ignore your child’s development because he or she is still tall or high. When you are precocious, your height is often higher than that of your peers, but you will stop growing early, so your height may be shorter in the future. Once puberty is over, growth will stop and no more treatment is possible.
6. The most accurate way to predict adult height is through accurate assessment of bone age. Because only the parents’ height is considered when calculating the genetic height, the child’s current height and bone age at that time are not considered. If the bone age is greater than the age, there will be less room for growth later in life and the adult height will be lower, while if the bone age is less than the age, there will be more room for growth later in life and the adult height may be higher. Since bone age is the physiological age of a person, it should match the current actual age. If the difference is too large, it is often caused by disease and requires timely examination and treatment.
7.First of all, in Japan, and now also in Taiwan and some Western European countries, free bone age films are taken every two years for all children and adolescents during their growth period, so that abnormalities in growth and development can be detected in time for timely treatment.