WHO Child Growth Standards

Recommendations

To monitor U.S. children's growth, CDC and the American Academy of Pediatrics recommend that health care providers in primary care settings use:

• WHO growth standard charts for children from birth to 2 years, regardless of the type of feeding.
• CDC growth reference charts for children 2 years and older.

The WHO growth charts represent growth standards that describe how healthy infants and young children should grow under optimal environmental and health conditions. The WHO growth charts were designed to be an international standard for infants and young children.

Online training

The WHO Training Course on Child Growth Assessment is intended for health care providers who measure and assess the growth of infants and young children or who supervise these activities. The course teaches how to measure weight, length, and height; interpret growth indicators; investigate causes of growth problems; and counsel caregivers.

Advantages

Using the WHO growth standards from birth to 2 years has several advantages over the CDC growth charts for children of the same age. WHO growth charts:

• Are standards that show how children should grow under optimal conditions.
• Use growth of breastfed infants as the norm for growth.
• Were created with longitudinal length and weight data measured at frequent intervals.123

Available growth charts

CDC's adapted versions of the WHO growth charts for children younger than 2 years are available online. They display both U.S. customary units and metric units. For boys and girls aged birth to 2 years, they include:

• Length-for-age and weight-for-age.
• Weight-for-length.
• Head circumference-for-age.

The WHO growth charts as modified by CDC use the 2nd percentile and the 98th percentile as the outermost percentile cutoff values. For children younger than 2 years:

• Low weight-for-length: weight-for-length that is less than the 2nd percentile for age and sex.
• High weight-for-length: weight-for-length that is higher than the 98th percentile for age and sex.
• Short stature: length-for-age that is less than the 2nd percentile.

Transitioning from WHO to CDC growth charts

When transitioning from the WHO growth standard charts to the CDC growth reference charts at 2 years, the growth classification may change. During this transition, use caution in interpreting any changes in classification.

Classification

During the transition from one chart to another, children may have a different classification because of a change from:

• Recumbent length to standing height measurements.
• Breastfed reference population to a primarily formula-fed reference population.
• Weight-for-length chart to BMI-for-age chart.
• One set of cutoff values to another.

Interpret changes with caution

During this transition, health care providers or other users of growth charts should interpret any changes in a child's percentile classification with caution. Growth measurements can be used in conjunction with medical and family history if abnormal growth is identified.

Growth monitoring is based on a series of accurate measurements over time. This series of measurements accounts for both short- and long-term conditions and provides context for interpreting an individual measurement.