Growth rates: what they are and how to read the values
The growth percentiles are values on the basis of which the pediatrician, at the end of pregnancy and during the usual medical examinations, is able to establish the level of growth of the child's body.
To then calculate these values, we start from the weight and height of the children divided by sex and age, and in the case of newborns in the first months, the head circumference is also measured.
The tables that enclose the values of the growth percentiles give life and the graphs constructed as follows: 100 groups are created made up of thousands of children of the same age and of the same sex that make up the representative sample.
Find out in this short video how big a baby is month by month.
After weighing them, they are placed in a row from the most frail to the most robust and divided according to their characteristics. Once this is done each group is a "centile" and the curve of the graph approaching the 50th percentile represents the population mean.
Your boy or girl will belong to one of these groups, or rather to a centile: the closer the percentile of membership is to the 50th, the more the child will approach the average characteristics of the population.
In a nutshell, in this way the average reference values are defined, so that the pediatrician can understand how your baby's growth is going. It will then keep the weight under control from the first month of life, especially in the case of newborns, while height, on the other hand, acquires more importance as the age progresses.
There is a table and a graph with specific growth curves for pathology, in this case they are useful for following the growth of particular groups of patients suffering from certain pathologies (an example: patients with Down Syndrome).
See also
How does the visit take place to record the child's growth?
The body growth of each individual is not always the same, but follows a quite different path that must be kept under control. Boys and girls grow differently, depending on the age you can observe an immeasurable growth, on the contrary, in other periods, the growth can be slowed down.
To record the growth data of your child it is advisable to periodically go to the pediatrician already in the first month of life for an in-depth examination. What specifically does the pediatrician do to take the measurement?
First of all, weigh the child: for this operation it is important to take off the clothes, which could negatively affect the final value.
Subsequently, the pediatrician will take care of measuring the height, and finally, only in the case of infants up to 1 year of age, the head circumference will be measured.
Once the pediatrician finds the numbers, he inserts them on the graph relating to the centiles and so he will proceed with the subsequent visits until the values cross and form the so-called growth curve.
In this way, by observing the curves, it is very easy to understand if your child's development is progressing well from birth or if it is necessary to intervene by investigating the situation further through specific tests.
Abrupt changes in the growth curve can mean several things, so it's important to always keep an eye on the numbers.
Growth curves: how to interpret the data
If as a parent you are wondering how to interpret your child's growth data, do not worry: we want to reassure you by saying that it will be the pediatrician himself who will keep you informed of any changes or anomalies.
We can generally say that if the growth curve observed in the percentile graph has a regular trend, it means that the child is growing in a constant and suitable way for its context.
If, on the other hand, it is possible to highlight deviations from the reference value, the pediatrician himself will evaluate the advisability of carrying out tests.
If your child is growing differently than the reference values of the growth percentile table, you should not be alarmed, it does not necessarily mean something.
There are so many factors at play to consider. A few examples? Genetics and family "history" mean that a child is much taller or heavier, or on the contrary, shorter or lighter than the average person. Much therefore depends on descent and ancestors, but sex also affects: the boy and the girl have totally different developments.
The cases of children or newborns whose values differ from the average since birth and for at least the first year of age, are usually followed a little more by the pediatrician, to exclude that the differences in numbers are not associated with some pathology .
Why are growth percentiles useful?
First of all, the growth percentiles allow the comparison between different parameters of the same individual: normally there must be a certain harmony between weight and height, but even in these cases there are other factors to consider.
The proportion must remain as unchanged as possible over time: if there is an excessive weight / height disproportion in relation to age, there could be a problem; a clear example in this case is obesity, where in the table the percentiles weight are much greater than those of height.
Not to be underestimated is a relative disproportion between the values of:
- head circumference of the child (important to avoid brain growth abnormalities)
- stature or height (which in the case of the newborn is called length)
- weight
These data fully reflect the particular physical structure of a boy and a girl, together with all the characteristics often found in parents.
In any case, the percentile data must always be evaluated and interpreted by the pediatrician who takes into account:
- the weight and height of the child or infant
- gestational age (i.e. the number of weeks of pregnancy)
- the height and constitution of the parents
- the general health of the child
It is good to know that every child has his own times and his own growth model: only the doctor can be able to assess whether growth and development are proceeding in the right direction.
The growth percentiles in Italy and in the world
Up to here we have analyzed how the measurement of the growth of children and infants works through the tables and graphs of growth percentiles, then underlining that each will belong to a different percentile.
Italian pediatricians use the World Health Organization percentile tables drawn up and updated periodically based on studies on population samples.
The US Centers for Disease Control or rather the Centers for Disease Control and Prevention (CDC), bodies responsible for verifying possible outbreaks of epidemics that would inevitably change the values of the percentile graphs, are also fundamental in identifying the growth curves. growth.
At this point it remains for us to consider that these percentile tables vary from one ethnicity to another and the numbers are different depending on the geographical area in which you are born. Europeans and North Americans are usually higher also thanks to a better standard of living than, for example, the African one.
An advice is always valid: you can make comparisons with the children of other parents, it will be a normal and automatic thing, you will wonder why your child is shorter than the height of another child, but as a mother remember that growth is subjective and always different. So the table with the percentile of your boy or girl's membership is only a rough indication.
