What Does that Growth Chart Mean?

Today’s post is brought to you by Prakar Poudel, International Medical Graduate, Future Pediatrician!

Growth is what makes children unique.

Everyone from Grandma to your neighbor watches the growth and development process from the moment your child is born until they become a fully mature adult. Natural laws dictate that the growth of each child is a unique, continuous and orderly process, although the different parts of a child can grow at different rates!

It is essential for your pediatrician to monitor the growth of your child until they are through adolescence, because changes in growth could be a sign of medical illness.

The most common measures to track are weight and height. However, the eruption of teeth and measurement of head circumference, chest circumference, mid-upper arm circumference and body mass index are other measures for tracking growth.

In general, a child:

  • doubles birth weight by age 6 months
  • triples birth weight by 12 months
  • quadruples birth weight by 2 years

Similarly, a child’s height:

  • will be around 50 cm (~20 in) at birth
  • will gain an additional 25cm (~10 in) by 1 year
  • 12.5 cm (~5 in) by 2 years, and
  • 10 cm (~4 in) by 3 years of age

One important note is that if growth in height is less than 4 cm (~1.6 in) per year after the age of 4 years, this suggests the child has a poor growth rate and needs a pediatrician’s visit.

The head circumference of a baby also increases at the rate of 2 cm (~.8 in) per month until 3 months of age and 2 cm per 3 months until 12 months of age.

If the measurement of the mid part of the biceps (upper arm) is below 12.5 cm in a newborn, the child also needs immediate medical attention. Average biceps size is in the graph below:

Lastly, teeth can also be considered a vital measure to track the child’s growth. As the child grows, primary (temporary) teeth erupt and fall in synchrony with the eruption of permanent teeth. All the temporary teeth fall and get replaced by permanent teeth by the age of 12 years.

Each child’s growth rate and velocity will be different and unique, so the Center for Disease Control (CDC) has created growth charts for weight, height and head circumference for each sex and age to monitor the overall growth of your child. The charts shown below are an example of growth charts of weight for age in boys and girls. All other kinds of growth charts can be found in your nearby children’s doctor.

A single appropriate growth chart is used for each child. The important part of plotting in these charts is that your child should be following a consistent percentile for it to be considered adequate growth. If your child’s weight crosses at least 2 percentiles – say falls from 75th percentile to the 25th – your child may need to see a pediatrician.

Any worries? Pediatricians love this stuff – call yours!