When to Start Growth Charts
Growth charts should be started at birth for all infants, regardless of gestational age. 1, 2
Chart Selection by Age
For infants from birth through 23 months of age, use the WHO growth charts. 1, 2 The CDC, in collaboration with the National Institutes of Health and American Academy of Pediatrics, established this as the standard of care in the United States. 2
At 24 months of age, transition to CDC growth charts, which continue through 19 years. 1, 2 This transition point is appropriate because the methods used to create WHO and CDC charts are similar after 24 months, allowing continuous monitoring throughout childhood without further chart changes. 2
What to Plot at Birth
Begin plotting the following measurements immediately after delivery:
These three parameters should be measured at every well-child visit and plotted on the appropriate growth chart. 2
Key Implementation Details
Use postnatal clinical measurements, not prenatal ultrasound data, when plotting growth charts. 3 While antenatal information about fetal growth restriction should be integrated into identifying newborns at risk, intrauterine charts should not be used to evaluate birthweight to maintain consistency with postnatal charts used in neonatal practice. 4
For preterm infants, use gestational age-corrected plotting until 24 months of age. 3 The WHO charts accommodate infants born at various gestational ages and allow tracking from birth through the neonatal period and beyond. 2
Critical Thresholds for Screening
When using WHO charts (birth to 24 months), use the 2.3rd and 97.7th percentiles (±2 standard deviations) to identify potentially abnormal growth, not the traditional 5th and 95th percentiles. 1, 2 Values below the 2.3rd percentile indicate potential adverse health conditions requiring immediate attention. 5
After transitioning to CDC charts at 24 months, the 5th and 95th percentiles are typically used as cutoff points. 2
Common Pitfalls to Avoid
Do not wait for symptoms to begin growth monitoring—start at birth. 1, 2 Growth charts have been used for over a century as essential screening tools to assess adequate nutrition and identify adverse health conditions early. 1
Recognize that single measurements are insufficient; serial measurements over time are essential. 3, 2 Growth velocity and trajectory matter more than percentile position alone. 3
Be aware that the transition from WHO to CDC charts at 24 months can create slight discontinuities in how a child's growth is classified. 2 This is expected and does not indicate pathology if the child maintains parallel growth along their curve. 2