Child growth

WHO standards (used here for under-2) describe how children should grow under optimal conditions, based on breastfed children worldwide. CDC charts describe how American children actually grew. For infants, WHO is generally preferred. For older children, either works.

Pediatricians track not just size but rate of growth. A child growing 2 inches/year when peers grow 2.5 inches/year might be falling behind even if still within normal percentiles. Velocity charts catch problems earlier than size charts alone.

Growth charts become less reliable during puberty because children enter puberty at different ages. An early bloomer might jump to the 90th percentile at 11, then be passed by late bloomers who keep growing until 18. Pubertal timing is largely genetic.

Under 2 years: Weight-for-length (doesn't require knowing exact age). Ages 2-20: BMI-for-age. For specific measures like height-for-age or weight-for-age, your pediatrician has additional charts.

There's no target percentile. Healthy children exist across the entire range from 5th to 95th. What matters is that your child grows consistently along their own curve, whatever that curve is.

Not necessarily. A child at the 10th percentile with parents at the 10th percentile is likely following genetic patterns. A child who drops from the 50th to the 10th percentile needs evaluation. Consistent tracking is reassuring; sudden changes warrant attention.

Pediatricians measure at each well-child visit — typically more frequently for infants (several times in year 1) and annually for older children. More frequent home measuring isn't necessary and may create unnecessary anxiety over normal fluctuations.