What are Percentiles?

CDC Girls 0-36 month Growth Chart

Percentiles are the most common method for tracking a child’s size and growth patterns. They are measurements that show how a child compares to children of their same age and gender. More specifically, they tell you the percent of children whose height and weight measurements are equal to or exceed you child’s height and weight. The 50th percentile is the average.

For example, if you have a 5-year-old daughter whose weight is at the 25th percentile, she weighs the same or more than 25 percent of other 5-year-old girls, and weighs less than 75 percent of other 5-year-old girls.

Most doctors will tell you that where your child’s measurements fall on the growth chart is not as important as whether they continue to grow along a similar percentile. Some children are just smaller or larger than other children their age. This does not mean that their growth isn’t normal or healthy.

It is important to understand your child’s growth and to monitor whether there are changes in their height and weight percentiles over time.

What do I do if my child is below the 5^th or above the 95^th percentile?

If your child’s height and weight above the 95th percentile or below the 5th percentile, your health care provider may monitor your child’s growth very closely. According to Dr. Vincent Iannelli, author of the Pediatrics Guide on About.com:

“Even if your child is at the 5th percentile for his weight, which means that 95% of kids his age weigh more than he does, if he has always been at the 5th percentile, then he is likely growing normally. It would be concerning and it might mean there was a problem with his growth if he had previously been at the 50th or 75th percentile and had now fallen down to the 5th percentile.”

Special Concerns

It is important to know that if your child was a low or very low birth weight baby or has a health condition that affects their growth, standard growth charts may not be appropriate. Ask your doctor about growth charts for children with special health care needs, which reflect growth patterns for children with similar conditions.

If you are concerned about your child’s growth for any other reason, talk with your child’s health care provider.