Growth charts are essential tools for monitoring infant development and well-being. For parents and providers working with breastfeeding dyads, understanding the history, purpose, and appropriate use of growth charts—especially the WHO Child Growth Standards—is key to supporting optimal growth without unnecessary interventions or concerns.

A Brief History of Growth Charts

The idea of tracking child growth has been around for over two centuries, rooted in efforts to reduce infant mortality and improve child health outcomes. In the early 19th century, physicians began collecting infant weight and height data to better understand the links between early growth and survival. Notably, Adolphe Quetelet, a Belgian mathematician and statistician, was among the first to compile and graph growth data, introducing the concept of the “average man” or l’homme moyen—an early attempt to quantify normal growth (Weaver, 2011).

By the mid-1800s, as infant mortality rates remained high and malnutrition was recognized as a public health issue, systematic efforts emerged to weigh and measure children. These were often conducted in foundling homes or orphanages. The idea that malnutrition and improper feeding could be detected through growth curves gained traction in the medical and public health communities (Weaver, 2011).

With the rise of statistical sciences and the development of the “numeric method,” growth charts began to be produced using large-scale data sets. Yet, these early charts were descriptive—they simply recorded how children were growing under existing conditions, not how they should grow under optimal health conditions. They reflected the average of children in specific populations, many of whom were formula-fed and lived in industrialized, often inequitable environments.

The Original US Growth Charts

For much of the 20th century, growth charts continued to evolve, often produced by national health authorities. For example, the Centers for Disease Control and Prevention (CDC) developed widely used charts in the U.S. based on data collected between 1963 and 1994.

In the U.S., growth charts produced by the National Center for Health Statistics (NCHS) in the 1970s and updated by the Centers for Disease Control and Prevention (CDC) in 2000 became the most widely used references for child growth.

However, these charts had critical limitations, particularly in how they represented feeding practices and demographic diversity.

Key Characteristics of the Original CDC/NCHS Chart Population:

• Predominantly formula-fed: A large proportion of the infants in the datasets were fed formula. Breastfeeding rates in the U.S. were low during the mid-20th century, especially during the periods of data collection (1963–1994). As a result, the charts primarily reflected the more rapid weight gain patterns of formula-fed infants, especially after 3–4 months of age.

• Mostly white, middle-class, U.S.-born children: The datasets used for the CDC growth charts disproportionately reflected white, middle-income families in the United States. They did not capture the full range of ethnic, socioeconomic, and cultural diversity found in the global population—or even within the U.S. population.

• Not health-optimized environments: Children included in the surveys came from the general population and were not screened for health status or optimal environmental factors. Some had exposure to smoking, limited access to healthcare, or lived in households with dietary or environmental constraints.

Implications for Breastfeeding

Because formula-fed infants gain weight more quickly than breastfed infants—especially in the second half of the first year—these charts made normal breastfed growth appear suboptimal. Breastfed infants often fell below the “expected” weight percentiles, prompting:

• Early supplementation

• Unnecessary weaning

• Misdiagnosis of “failure to thrive”

• Undermining of confidence in breastfeeding

For decades, growth assessment tools were unintentionally biased against breastfeeding, simply because they were based on the wrong reference group.

The WHO Multicentre Growth Reference Study (MGRS)

Recognizing the need for a growth chart based on optimal growth, not just average growth, the World Health Organization (WHO) launched the Multicentre Growth Reference Study (MGRS) from 1997 to 2003. This study was groundbreaking in both its design and its goals.

Key Features of the WHO Study Population:

• Exclusively or predominantly breastfed: All infants were breastfed for at least four months and continued to breastfeed for at least 12 months, with appropriate complementary foods introduced after six months.

• Geographically diverse: The study included healthy children from six countries—Brazil, Ghana, India, Norway, Oman, and the United States—representing a broad range of ethnicities and cultural backgrounds.

• Health-optimized environments: Families lived in environments that supported optimal health and development. Mothers were nonsmokers, healthcare access was consistent, and sanitation, nutrition, and psychosocial support were considered ideal.

• Longitudinal design: Children were followed from birth to five years with careful measurements taken by trained teams using standardized techniques.

These characteristics allowed the WHO to develop prescriptive growth standards—charts that describe how children should grow under optimal conditions, rather than simply how they typically grow in any given population

WHO Growth Chart: The Global Standard

In 2006, the WHO Child Growth Standards were released and quickly became the recommended tool for growth assessment in children under 5 years of age. These standards:

• Reflect the normal growth trajectory of breastfed infants, especially the natural slowing of weight gain after 3–4 months.

• Allow for global applicability, offering a unified standard for child health monitoring across countries, cultures, and ethnic groups.

• Promote breastfeeding as the biological norm, ensuring that growth assessments support, rather than undermine, optimal feeding practices.

Global Adoption and Ongoing Debate

The WHO charts have been adopted in over 140 countries, and are recommended by leading health authorities, including:

• The American Academy of Pediatrics (AAP), which endorses using the WHO charts for infants and children aged 0–24 months.

• The Centers for Disease Control and Prevention (CDC), which recommends the WHO charts over its own CDC 2000 charts for infants in the first two years of life.

However, some countries and researchers have noted discrepancies between WHO curves and local population data, especially in East Asia and parts of Europe. For instance, Korean researchers found that WHO percentiles may not align well with national averages, prompting interest in region-specific references (Kang et al., 2021).

Still, the WHO charts remain the best available international standard because they represent optimal, not average, growth and reinforce breastfeeding as the global norm.

Why This History Still Matters Today

Understanding the origins of growth charts is essential for anyone working with infants, particularly those who support breastfeeding. When growth charts were based on a non-representative population, breastfeeding often appeared to be the problem. Now, with the WHO standards, we have a more accurate lens through which to view infant growth and a better foundation for supporting breastfeeding success.

When we use growth charts that reflect optimal conditions—including breastfeeding—we avoid unnecessary interventions and promote confidence in the feeding relationship.

References

Weaver, L. T. (2011). How did babies grow 100 years ago? European Journal of Clinical Nutrition, 65(1), 3–9. https://doi.org/10.1038/ejcn.2010.257

Kang, S., Lee, S. W., Cha, H. R., Kim, S. H., Han, M. Y., & Park, M. J. (2021). Growth in exclusively breastfed and non-exclusively breastfed children: Comparisons with WHO child growth standards and Korean national growth charts. Journal of Korean Medical Science, 36, e315. https://doi.org/10.3346/jkms.2021.36.e315

Oliveira, M. H., et al. (2022). Accuracy of international growth charts to assess nutritional status in children and adolescents: A systematic review. Revista Paulista de Pediatria, 40, e2021016. https://doi.org/10.1590/1984-0462/2022/40/2021016

Zemel, B. S. (2023). From growth charts to growth status: How concepts of optimal growth and tempo influence the interpretation of growth measurements. Annals of Human Biology, 50(1), 236–246. https://doi.org/10.1080/03014460.2023.2189751

Centers for Disease Control and Prevention (n.d.). Using the WHO Growth Charts. https://www.cdc.gov/growth-chart-training/hcp/using-growth-charts/who-methodology.html