anthropometry

Child Growth

How the Child Grows

The growth of the child consists of a set of bodily changes that allow him to acquire, at the end of puberty, the anatomical, physiological and morphological traits typical of adulthood.

The growth, therefore, does not represent a simple increase in the size of the body, but also a progressive modification of forms and body composition. In the growing child, for example, the relationships between the different skeletal segments are very different from those of an adult. In the newborn, in particular, the head represents about a quarter of the entire body length, while at the end of skeletal maturation this ratio drops to 1/7 or 1/8.

When born, the newborn is about 50 centimeters long, with an average weight of 3400 grams and a head circumference of 35 cm. Twenty years later his body will have grown 3 and a half times in length and about 20 times in weight.

The duration of growth is so much higher as sexual maturity is reached later; obviously the inverse discourse is also valid.

If we show the growth of the child in a graph, we will see that this occurs according to different methods and rhythms depending on the body district studied.

Furthermore, if we consider a single parameter, as may be the statural growth, we note that it does not follow a linear and constant trend over time; in the specific case, the rate of growth is maximum in the first months of life, decreases up to 2-3 years, stabilizes and after ten springs undergoes a last, notable increase.

Insights

Fetus developmentChild growthBreast growthBeight adult statureWeight growthPerfect of growth

Growth in Height

As anticipated, the child's body grows rapidly in the first year of life, increasing, in terms of length, by 50% compared to neonatal values. To these first 25 cm, another 12-13 will be added at the end of the 24th month.

From this moment on the statural growth rate remains relatively constant (+ 5-6 cm / year). At the age of four, the child will have doubled his height (about 100 centimeters); it will only triple it 8 years later (150 centimeters).

In the prepubere period there is, both in the male and in the female, a clear statural snap (+ 8-12 cm / year for two or three years) that persists until sexual maturity is reached.

This rapid growth in stature is anticipated in the females (it starts around 9 and a half years, reaches the peak at 12 and ends around the 14), while in the boys it is a little more delayed (from 11-12 years up to 16, with peak around 14). For this reason, between 11 and 14 years, females outnumber males.

Around the sixteenth and a half years of age for the females, and one year later for the males, the boy will have reached about 98% of the final height; will complete it in the next 24 months.

The evaluation of the height of the parents allows to calculate, with simple mathematical operations, the so-called "target zone", that is to say the definitive stature, or genetic target, foreseen in adulthood (see dedicated article). This is obviously average data, which may vary slightly from individual to individual.

In any case, the detection of height must be as accurate as possible since even a modest imprecision (eg 1-2 cm) can distort the interpretation of the collected data. For this reason it is good to remember that the evaluation of the child's growth must always and in any case rely on the experience and competence of the pediatrician.

Weight Growth

At birth, the weight appears to be quite variable (from 2.7 to 4.5 kg). In the following days the newborn suffers a weight loss of about 5-10% of the initial weight, due to dehydration, sometimes insufficient food intake (colostrum) and dehydration. After this period, within ten days, the newborn quickly regains the lost weight and proceeds with the growth. Already at 4-5 months its body mass is doubled, while at the first candle it will even be tripled.

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Similar to what described for stature, the rate of weight growth is reduced in the second year of life, flattening until puberty (+2.5 kg / year). The adolescent release (+6/7 Kg) follows the statural increase, reflecting the skeletal growth and the muscular and fat development induced by the sex hormones.

Preventing childhood obesity by educating the child about proper nutrition and regular exercise (compatibly with his preferences) is extremely important. This is because an obese child has great chances to remain so for the rest of his life, with all the physical and psychological consequences of this, certainly not a happy condition.

Monitoring of the nutritional status of the child takes place by detecting the adipose folds, whose thickness reflects the variations of the subcutaneous adipose tissue. As shown in the figure to the side, the development of the fat mass follows a particular pattern: it begins to increase around the 34th postmestral week, until it reaches a peak nine months after birth; therefore it tends to decrease up to the 6th - 8th and, from this period onwards, it differs in the two sexes (both as quantity and distribution).

Growth of body systems and growth percentiles ยป