They Grow Up So Fast: A Parents’ Guide to Growth Charts

Since 1977, health care providers in the U.S. have been using pediatric growth charts to see how kids stack up. It’s important to track a child’s growth rate over time, but keep in mind that no one number tells the whole story.

Choosing a Chart

For children up to age 2, the growth charts from the World Health Organization (WHO) are the gold standard, according to the Centers for Disease Control and Prevention (CDC). To develop these charts, researchers looked at optimal growth patterns for young children in six countries—including the U.S. The charts take into account the growth patterns for infants who are mainly breast-fed for at least four months and who are still breast-feeding at 12 months.

The WHO charts are designed to be used for children of any ethnicity and socioeconomic status, regardless of whether they are breast-fed or formula fed. Some of the indicators measured include weight for age, weight for length/height, head circumference for age, and triceps skinfold (the amount of skin that can be pinched on the back of the upper arm) for age.

After 2 years of age, you can switch over to using the CDC growth charts as a guide. These charts can be used all the way through young adulthood, up to age 19. To see the charts, visit cdc.gov/growthcharts.

How to Read the Charts

Here’s how growth charts work. Let’s say you want to look at the height of your son based on his age, and he’s 3 feet, 5 inches tall at 4 years old. You would find the stature-for-age chart for males. On the left side, look for the entry that’s closest to his age. Once you find that row, look across to find his height. Then, follow that column up to the top to find his percentile. In this example, the boy is just under the 75th percentile, which means he is as tall or taller than 75 percent of all 4-year-old boys, and shorter than 25 percent of them.

Keep in mind that a growth chart is just one item in a pediatrician’s and parent’s toolkit to measure how a child is developing. If you have any concerns, talk with your child’s doctor. He or she will use the growth charts to monitor your child over time. For instance, if your daughter has always been in the 50th percentile for weight and suddenly drops down to the 10th percentile, that might be a sign that something is wrong. But if she has always been near the 10th percentile, and her parents are on the smaller side, her weight may be just fine.

Remember, a percentile isn’t like a grade in school. Higher or lower isn’t better—it all depends on how your individual child is growing.