Normal Growth

Normal growth is one of the best indicators of good health and nutrition. Normal heights and weights, however, are difficult to define. Short parents tend to have short children. Tall parents tend to have tall children. For any given height, an ideal weight can be determined from a growth chart. An infant with failure to thrive is underweight for his height. An obese child is overweight for his height.

Your physician will weigh and measure your child on each visit and plot these numbers on a standard growth chart. Your child's growth rate over time reveals the most about his or her physical health.

The following facts and figures may answer some of your questions about normal growth.

Average newborn (full-term)

Weight: 7 pounds, 5 ounces (normal range: 6 to 10 pounds)

Length: 20 inches (50 cm) (normal range: 18 1/2 to 21 1/2 inches)

Head circumference: 13.8 inches (35 cm) (normal range: 33 to 37 cm)

A premature baby weighs less than 5 and 1/2 pounds (2.5 kilograms).

Average weights at different ages

5 months: double birth weight

12 months: triple birth weight

2 years: quadruple birth weight

1 to 6 years: weight in pounds = (age x 5) + 17

7 to 12 years: weight in pounds = (age x 7) + 5

Average heights at different ages

4 years: double birth length

13 years: triple birth length

2 to 14 years: height in inches = (age x 2 1/2) + 30

(Remember: 1 foot = 12 inches; 1 inch = 2.5 centimeters)

Predicting adult heights

 
                                Age
                     ------------------------    Multiply
                       Boys            Girls        by
---------------------------------------------------------
1/2 adult height
  is reached at      27 months      20 months       2

2/3 adult height
  is reached at       6 years        5 years        1.5

3/4 adult height
  is reached at       9 years        7 years        1.3
---------------------------------------------------------

Another formula is:  adult height (boys) = 1.87 x height
                     at age 3 years

                     adult height (girls) = 1.73 x height
                     at age 3 years