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Down Syndrome Growth Chart Calculator

Z-score and percentile calculator using Zemel 2015 growth charts for children with Down syndrome (Trisomy 21). Select infant (0–36 months) or pediatric (2–20 years) reference.

How to interpret Down syndrome growth charts

Standard WHO and CDC charts do not reflect typical growth patterns in Down syndrome. Zemel 2015 charts provide syndrome-specific medians and percentiles for weight, length/height, and head circumference. Plot serial measurements against the appropriate age band (infant vs pediatric).

Interpret percentiles in context of feeding, cardiac disease, thyroid function, celiac screening, and developmental progress. A single percentile is not diagnostic; trend and clinical assessment matter.

Sources and Reference Basis

Zemel 2015 LMS parameters for Down syndrome growth. Use syndrome-specific charts rather than standard pediatric references when assessing children with Trisomy 21.

Frequently Asked Questions

Why use Down syndrome–specific growth charts?

Children with Down syndrome have different growth trajectories than the general pediatric population. Syndrome-specific charts avoid misclassification as failure to thrive or overweight.

Which Zemel chart should I select?

Use the infant chart (0–36 months) for young children and the pediatric chart (2–20 years) for older children and adolescents.