Length is the quiet measure. It moves slowly, so a length percentile should be read over months, not weeks — and a line that climbs gently is often just catching up.
Length percentile basics
Length-for-age ranks your baby's length against healthy same-age, same-sex babies on the WHO curve. Most babies sit between the 3rd and 97th percentile.
Slow is the default
Length changes in centimeters, not bursts. A baby can hold the same length percentile for months — that is the expected pattern, not a stall.
Gentle climbs are normal
Some babies, especially born small or early, climb length percentiles gradually over the first years. As long as the climb is steady and not a sudden jump, it is usually a good sign.
Keep the long view
GrowChart plots length-for-age on the WHO curve with the full history, so a slowly moving line is seen for what it is: steady progress.
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