{
  "abstract": "We investigated the robustness of the INTERGROWTH-21st Preterm Postnatal Growth Standards for monitoring the postnatal growth of preterm infants a decade after the original study that produced them. The INTERPRACTICE-21st Study assessed the early postnatal growth of all infants born preterm in 15 study sites across 14 countries. From this sample, we selected a 'standard-like' cohort of mother-newborn dyads as in the original study. Thus, we selected all singleton babies of healthy mothers, born between 27 and < 37 weeks' gestation, without congenital malformations, fetal growth restriction or severe postnatal morbidity, i.e. confirming their eligibility for inclusion in the original standards. We used, across all study sites, the same standardised anthropometric measurements and feeding practices based on human milk. The main outcomes were the skeletal, fat-free mass indicators head circumference and length, following WHO recommendations. Variance component analysis and second-degree fractional polynomial regression models in a multi-level framework accounting for repeated measures were used to compare the growth trajectory of the 'standard-like' cohort to the standards. Of 3634 preterm babies enrolled, 1998 were singletons with complete birth anthropometric data. Among these, 1073 (54%) mother-baby dyads met the 'standard-like' eligibility criteria. The between-site differences in early postnatal growth of head circumference and length accounted for only 10.2% and 12.7% of the total variability of these repeated measures, proportions considerably lower than those for the total between individuals within a site variance of 80% and 79%, respectively. These low proportions supported pooling data across study sites and reinforced the consistency of the original results across geographical settings.Conclusion\n\nThe early growth of healthy preterm infants in the INTERPRACTICE-21st 'standard-like' cohort, assessed a decade after the original study, closely matched the pattern originally described by the INTERGROWTH-21st standards, which appear therefore robust to geographical changes and time.What is known\n\n• The INTERGROWTH-21st Preterm Postnatal Growth Standards are the only international standards, based on the WHO prescriptive approach, for monitoring the growth of preterm infants. They were produced by following, from early pregnancy, uncomplicated preterm infants who were born to healthy mothers and achieved adequate growth and development at age 2.What is new\n\n• In a study conducted in 14 countries worldwide, skeletal growth trajectories in a contemporary \"standard-like\" cohort of preterm infants demonstrated much larger within, than between, study site variance and closely matched the INTERGROWTH-21st standards, supporting the consistency of preterm growth across populations and over time.",
  "abstract_shown": true,
  "affiliations": [
    "Neonatal Special Care Unit, Regina Margherita Children Hospital, Turin, Italy. giuliani.pediatria@gmail.com.",
    "Nuffield Department of Women's & Reproductive Health, University of Oxford, Oxford, UK. giuliani.pediatria@gmail.com.",
    "Center for Environmental Research and Community Health, School of Public Health, University of California, Berkeley, USA.",
    "Paris Cite University, APHP Hôpital Universitaire Necker-Enfants Malades, Paris, France.",
    "Department of Pediatrics, Federal University of Minas Gerais, Belo Horizonte, Brazil.",
    "Nuffield Department of Women's & Reproductive Health, University of Oxford, Oxford, UK.",
    "Neonatal Intensive Care Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.",
    "Neonatal Intensive Care Unit and Paediatric Department, Santa Croce Hospital, Moncalieri, Italy.",
    "Neonatology Unit, Hospital Sant Joan de Deú, Barcelona, Spain.",
    "Instituto Nacional de Perinatología \"Isidro Espinosa de los Reyes\", Mexico City, Mexico.",
    "Division of Woman & Child Health, Dept of Paediatrics and Child Health, The Aga Khan University, Karachi, Pakistan.",
    "Division Neonatología, Hospital Materno Infantil Ramón Sarda, Buenos Aires, Argentina.",
    "The Aga Khan Hospital, Nairobi, Kenya.",
    "Department of Pediatrics, Division of Neonatology, Dokuz Eylul University Faculty of Medicine, Izmir, Turkey.",
    "Holy Family Hospital, Brong Ahafo Region, Techiman, Ghana.",
    "Neonatology Department, St. Johns Medical College Hospital, Bangalore, India.",
    "General Hospital With Extended Activity Prilep, Prilep, North Macedonia, UAE.",
    "Department of Clinical Nutrition and Dietetics, College of Health Sciences, University of Sharjah, Sharjah, UAE.",
    "Center for Obstetrics, Gynecology and Perinatology, Moscow, Russian Federation.",
    "Center for Global Child Health, Hospital for Sick Children, Toronto, Canada.",
    "Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 30,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Francesca Giuliani"
    },
    {
      "affs": [
        2
      ],
      "name": "Robert B Gunier"
    },
    {
      "affs": [
        3
      ],
      "name": "Alexandre Lapillonne"
    },
    {
      "affs": [
        4
      ],
      "name": "Maria Albertina S Rego"
    },
    {
      "affs": [
        5
      ],
      "name": "Adele Winsey"
    },
    {
      "affs": [
        2
      ],
      "name": "Stephen A Rauch"
    },
    {
      "affs": [
        6
      ],
      "name": "Paola Roggero"
    },
    {
      "affs": [
        5
      ],
      "name": "Maria Clara Restrepo Mendez"
    },
    {
      "affs": [
        7
      ],
      "name": "Sonia Deantoni"
    },
    {
      "affs": [
        8
      ],
      "name": "Montserrat Izquierdo Renau"
    },
    {
      "affs": [
        9
      ],
      "name": "Irma Alejandra Coronado Zarco"
    },
    {
      "affs": [
        10
      ],
      "name": "Shabina Ariff"
    },
    {
      "affs": [
        11
      ],
      "name": "Constanza Soto Conti"
    },
    {
      "affs": [
        12
      ],
      "name": "Roseline Ochieng"
    },
    {
      "affs": [
        13
      ],
      "name": "Funda Tuzun"
    },
    {
      "affs": [
        14
      ],
      "name": "Jacqueline Asibey"
    },
    {
      "affs": [
        15
      ],
      "name": "Chandrakala Bada Shekharappa"
    },
    {
      "affs": [
        16
      ],
      "name": "Gabriela Tavcioska"
    },
    {
      "affs": [
        17
      ],
      "name": "Leila Cheikh Ismail"
    },
    {
      "affs": [
        6
      ],
      "name": "Camilla Menis"
    },
    {
      "affs": [
        18
      ],
      "name": "Irina Ryumina"
    },
    {
      "affs": [
        11
      ],
      "name": "Ricardo Nieto"
    },
    {
      "affs": [
        5
      ],
      "name": "Josephine N A Agyeman-Duah"
    },
    {
      "affs": [
        9
      ],
      "name": "Brenda Frias Madrid"
    },
    {
      "affs": [
        18
      ],
      "name": "Marina Markelova"
    },
    {
      "affs": [
        2
      ],
      "name": "Brenda Eskenazi"
    },
    {
      "affs": [
        19
      ],
      "name": "Zulfiqar A Bhutta"
    },
    {
      "affs": [
        5,
        20
      ],
      "name": "Aris T Papageorghiou"
    },
    {
      "affs": [
        5,
        20
      ],
      "name": "Stephen H Kennedy"
    },
    {
      "affs": [
        5,
        20
      ],
      "name": "Jose Villar"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7bcxv3sf1f7pg.bib",
  "cited_by": 0,
  "doi": "10.1007/s00431-026-07494-1",
  "fulltext_url": "https://europepmc.org/articles/PMC13687238",
  "id": "7bcxv3sf1f7pg",
  "issns": [
    "0340-6199",
    "1432-1076"
  ],
  "landing_url": "https://europepmc.org/article/MED/42905282",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2916|Infant Nutrition and Health"
    ]
  ],
  "openalex": "W7223156640",
  "pdf_url": "https://europepmc.org/articles/PMC13687238?pdf=render",
  "pmcid": "PMC13687238",
  "pmid": "42905282",
  "published": "2026-10-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7bcxv3sf1f7pg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:53Z",
      "native_id": "MED:42905282",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42905282"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "journal-openalex:F27",
      "subfield": "general"
    }
  ],
  "title": "The INTERGROWTH-21st Preterm Postnatal Growth Standards are robust across geographical settings and time.",
  "title_text": "The INTERGROWTH-21st Preterm Postnatal Growth Standards are robust across geographical settings and time.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:53Z",
  "url": "https://research.draconitic.com/paper/7bcxv3sf1f7pg",
  "venue": "European journal of pediatrics",
  "versions": []
}