Growth Standards for Preterm Infants

2022 07 Projects FLRF

INTERGROWTH-21st Preterm Growth Standards are from the International Fetal and Newborn Growth Consortium for the 21st Century: a global, multidisciplinary network of more than 300 researchers and clinicians from 27 institutions in 18 countries, coordinated from the University of Oxford. 

Over the years the consortium has produced various growth standard recommendations which have been adopted globally. Yet growth and feeding protocols for preterm infants had been missing until now.  

The INTERGROWTH-21st Preterm Growth Standards, their distribution and training, are led by Professor Stephen Kennedy and Professor José Villar, supported by FLRF. The globally validated preterm infant growth standards, feeding protocols and tools and practical training materials are freely available to clinicians, researchers and policymakers.

Access the INTERGROWTH-21st Preterm Postnatal Growth Standards and Feeding Protocol here.


More about the INTERGROWTH-21st project

Measurement of preterm growth was based upon expected fetal growth whilst in utero. The resulting standards, tools and online training materials complement existing standards for pregnancy and newborn infants, with the aim of providing continuity from conception until five years of age.

The INTERGROWTH-21st project’s growth monitoring, educational and feeding resources have been translated into several languages, including English, Spanish, Italian, Russian and Portuguese, and the training toolkit is expanding. The tools and standards have been widely downloaded in 195 countries and a worldwide network of more than 400 hospitals and health institutions is using the preterm postnatal growth standards and feeding recommendations.

These new standards of care can support optimal growth of preterm infants and help clinicians and parents avoid overfeeding, reduce the risk of childhood overweight and obesity, and improve the early detection of infants with suboptimal growth. They also have the potential to alter World Health Organization policy in constructing and presenting preterm growth charts.

Read the press release

In 2021, FLRF extended its support of INTERGROWTH-21st through a follow-on project led by the University of Oxford Nuffield Department of Women’s & Reproductive Health called Growth and Development of Preterm Infants Across the World: How Breastmilk Influences Infant Outcomes in Different Preterm Phenotypes. 

Green LJ, Kennedy SH, Mackillop L, Gerry S, Purwar M, Staines Urias E, et al. International gestational age-specific centiles for blood pressure in pregnancy from the INTERGROWTH-21st Project in 8 countries: A longitudinal cohort study. PLoS Med. 2021;18(4):e1003611. DOI: 10.1371/journal.pmed.1003611

Ohuma EO, Villar J, Feng Y, Xiao L, Salomon L, Barros FC, et al. Fetal growth velocity standards from the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project. Am J Obstet Gynecol. 2021;224(2):208.e1-208.e18. DOI: 10.1016/j.ajog.2020.07.054

Fernandes M, Villar J, Stein A, Staines Urias E, Garza C, Victora CG, et al. INTERGROWTH-21st Project international INTER-NDA standards for child development at 2 years of age: an international prospective population-based study. BMJ Open. 2020;10(6):e035258. DOI: 10.1136/bmjopen-2019-035258

Drukker L, Staines-Urias E, Villar J, Barros FC, Carvalho M, Munim S, et al. International gestational age-specific centiles for umbilical artery Doppler indices: a longitudinal prospective cohort study of the INTERGROWTH-21st Project. Am J Obstet Gynecol. 2020;222(6):602.e1-602.e15. DOI: 10.1016/j.ajog.2020.01.012

Hirst JE, Knight HE, Ohuma EO, Dwyer T, Hennig BD, Papageorghiou AT, et al. Social gradient of birthweight in England assessed using the INTERGROWTH-21st gestational age-specific standard. Arch Dis Child Fetal Neonatal Ed. 2019;104(5):F486–92. DOI: 10.1136/archdischild-2018-315295

Villar J, Giuliani F, Figueras-Aloy J, Barros F, Bertino E, Bhutta ZA et al. Growth of preterm infants at the time of global obesity. Arch Dis Child. 2019 Aug;104(8):725-727. DOI: 10.1136/archdischild-2018-315006.

Villar J, Giuliani F, Barros F, Roggero P, Coronado Zarco IA, Rego MAS et al. Monitoring the Postnatal Growth of Preterm Infants: A Paradigm Change. Pediatrics. 2018 Feb;141(2). pii: e20172467. DOI: 10.1542/peds.2017-2467.

Villar J, Giuliani F, Bhutta ZA, Bertino E, Ohuma EO, Ismail LC et al. Postnatal growth standards for preterm infants: the Preterm Postnatal Follow-up Study of the INTERGROWTH-21st Project. Lancet Glob Health. 2015 Nov;3(11):e681-91. DOI: 10.1016/S2214-109X(15)00163-1.

Villar J, Ismail L, Victora C, Ohuma E, Bertino E, Altman D et al. International standards for newborn weight, length, and head circumference by gestational age and sex: the Newborn Cross-Sectional Study of the INTERGROWTH-21st Project. Lancet. 2014 Sep 6;384(9946):857-68. DOI: 10.1016/S0140-6736(14)60932-6.

Bhutta ZA, Giuliani F, Haroon A, Knight HE, Albernaz E, Batra M et al. Standardisation of neonatal clinical practice. BJOG. 2013 Sep;120 Suppl 2:56-63, v. DOI: 10.1111/1471-0528.12312.

Villar J, Altman DG, Purwar M, Noble JA, Knight HE, Ruyan P et al. The objectives, design and implementation of the INTERGROWTH-21st Project. BJOG. 2013 Sep;120 Suppl 2:9-26, v. DOI: 10.1111/1471-0528.12047.

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