A newborn's growth is assessed by observing three parameters over time: weight, height and psychomotor development, comparing them with the percentile charts of the World Health Organization. More than any single value, what matters is steady progress along the child's own curve. It is one of the topics that causes new parents the most anxiety: let's see how to read it calmly.
The three growth parameters: weight, height and psychomotor development
Growth is monitored by observing variations from the standard values of the percentile charts, divided by sex and valid up to 5 years of age. The milestones follow natural mechanisms that are similar in almost all children, but they should always be read taking into account individual differences: genetics, nutrition, environment.
Weight. It is one of the main indicators. At birth a newborn usually weighs between 2.5 and 4.5 kg. In the first days a physiological weight loss of about one tenth of the body weight is normal, usually regained within the first weeks.
Height (length). Length is also fundamental, but here the range between children is wider because heredity plays a big role. It can happen that during the first two years a child stays below average and then catches up quickly.
Psychomotor development. This is the most delicate parameter: it allows any motor difficulties to be spotted in time and must always be assessed by the pediatrician.
How to read the WHO percentile charts
The growth charts are updated periodically by the World Health Organization and are a reference for pediatricians and parents. A child in the 25th or 75th percentile is equally healthy: what matters is that they follow their own curve over time in a steady way. Any deviations should not cause alarm but should be assessed with your trusted pediatrician.
Growth milestones in the first years
In the first two years a child grows rapidly; from the second year onward the pace becomes more uneven, with pauses and catch-ups linked to individual factors, lack of appetite, seasons and minor illnesses. All of this is perfectly normal.
Growth spurts: what they are and how to recognize them
Growth spurts typically occur around the 2nd-3rd week, at the 6th week and toward 3 months, sometimes also at the 6th and 8th month. During these phases the newborn may:
- become insatiable and stay at the breast for a long time
- wake up more often at night
- seem fussy and restless
They last from a few days to a week. It is important to continue breastfeeding on demand, without adding other liquids that would give a false sense of fullness and reduce the demand for milk. As a reference, in the first weeks a gain of at least 140 grams per week is considered indicative.
Related products on BabyChic
Frequently asked questions about newborn growth
How much should they gain per week?
Roughly at least 140-200 g per week in the first weeks, but it is the progress over time that counts.
When to worry?
When the trend steadily departs from the curve or psychomotor development does not progress: in these cases always consult the pediatrician.
The information provided is for general guidance and does not replace the assessment of the pediatrician, the only reference for the child's growth and health.
