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Categories > Children’s Health > Growth and development

Not so fast: Determining your child’s height

Your nephew and your son are both 9 years old and were born only weeks apart, but your son looks so much shorter. Should you be worried?

Though many factors affect growth, much depends on the parents’ height. If your son’s health is normal, his shortness may be temporary. Here’s how your pediatrician might predict what a child’s adult height will be:

Boys: Add five inches to the mother’s height, then add this number to the father’s height. Divide by two. This is about how tall a boy should grow to be.

Girls: Take the father’s height and subtract five inches. Add this number to the mother’s height, then divide by two. This is about how tall a girl should grow to be as an adult.

If your son is near the growth curve suggested by the formula, rest easy. If not, your doctor may want to X-ray his hand and wrist to learn his “bone age.” Example: An 8-year-old who’s only as tall as an average 6-year-old should have bones like a 6-year-old. If so, growth is probably delayed, not stunted. Your doctor will test further if a deeper problem is suspected.