Height And Growth Charts For Your Growth PercentileWhat Do the Percentiles Mean? When you look at a growth chart, you will see seven curves that follow the same pattern. Each one represents a different percentile: 5th, 10th, 25th, 50th, 75th, 90th, and 95th. The 50th percentile line represents the average value for age. (There are also charts that show 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles. Doctors sometimes use these when they plot measurements that fall to the very outer edges of one or more growth curves). Your child's growth measurements will be plotted among these percentile curves. To better understand how to interpret those readings, consider these examples. An infant whose head circumference falls in the 90th percentile will be plotted right on the second curve from the top of the chart (the 90th percentile curve). Being in the 90th percentile means the child's head measurement is greater than or equal to the measurements of 90% of children that age in the country. The remaining 10% of infants that age have head measurements that exceed that child's. If a 4-year-old's weight at a checkup falls in the 20th percentile, that reading will be plotted between the curves for the 10th and 25th percentiles. That means 80% of children that age weigh more and 20% weigh less than that child. Now, you shouldn't assume that a high or low reading means there's a problem. A baby whose head circumference is in the 90th percentile might also fall in the 90th percentile for weight and length - he's just a normal kid who's large overall. (He could be the son of a 6-foot, 8-inch former linebacker!) The child whose weight falls in the 20th percentile may have parents who are a bit below average for height and weight. For him, being in the 20th percentile is an entirely normal reading. Sometimes, however, a child's measurement increases or falls sharply, or is at one extreme of the growth chart. For example, children who fall below the 5th percentile on the weight for stature (height) chart are considered underweight; children at or above the 85th percentile on this chart are considered overweight (and at risk for obesity); and those at or above the 95th percentile are considered to be obese. Generally, if a measurement exceeds the 95th percentile or crosses two percentile curves (such as climbing from the 40th percentile to the 75th percentile, thereby crossing the 50th and 75th percentile curves), there may be some cause for concern. On the other hand, if a measurement falls below the 5th percentile or crosses two percentile curves (dropping from the 50th to the 20th percentile, for instance), the doctor will also consider the possibility of a health problem affecting the child's growth. What Can the Charts Tell Me About My Child's Growth? Although growth charts are valuable tools, both doctors and parents must be careful not to focus too much on any one reading. Instead, the numbers should be viewed as a trend. Any measurement, taken out of context of the others, might give you the wrong impression of your child's growth. For example, a child's height measurement might place him at the 5th percentile, but this usually doesn't indicate a growth problem if his subsequent measurements continue to track along that percentile curve (as might be the case for a child who has inherited "short genes" from his parents). If the doctor and parents fixate on that one measurement, however, they might wrongly worry about the child's growth. When growth chart readings are examined over time, they reveal a pattern of development. That pattern lets you know how your child is growing in relation to other children his age and also shows you how he has progressed from previous measurements. This information is a much more useful indicator of whether a child is growing normally than any single measurement. |