BMI-for-age Newborn and Infant Assessment

There is no accepted definition of underweight, overweight, or obesity for children <2 years of age.

• For infants, BMI charts are used to screen for overnutrition and growth faltering, and are particularly relevant in term infants <6 months.
  
  • A comparative study of nearly 74,000 full-term infants found consistent agreement between BMI and weight-for-length from 6 months onward.
• For preterm infants, BMI-for-age as a measure of disproportionality or as a proxy for body fat postnatally is not well established 
• Charts
  
  • BMI-for-age birth to 2 years, percentiles (girls) (boys)
  • BMI-for-age birth to 2 years, z-scores (girls) (boys)
    
    

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