2026-08-24
Reading a growth chart without panicking
What a percentile does and does not mean, and why the line matters more than the number.
Growth charts cause more unnecessary worry than almost anything else handed to a parent, usually because a single number gets read as a grade.
A percentile is a comparison, not a score. A child on the 20th percentile is smaller than most children the same age, and that is a description rather than a problem. Some children are simply smaller, often for reasons visible at the next family gathering.
What is watched is the shape of the line over time, not where it sits. A child who has tracked steadily along the same curve is usually doing exactly what they should be, wherever that curve happens to be.
What draws attention is a change in direction: a line that was steady and then flattens or climbs sharply. That is worth a conversation, and it is why the clinic measures at intervals rather than once.
If a chart has worried you, bring it. Being told plainly that a line is fine is worth an appointment on its own, and being told early that it is not is worth considerably more.