Implications for quantifying early life growth trajectories of term-born infants using INTERGROWTH-21st newborn size standards at birth in conjunction with World Health Organization child growth standards in the postnatal period

TY - JOUR

T1 - Implications for quantifying early life growth trajectories of term-born infants using INTERGROWTH-21st newborn size standards at birth in conjunction with World Health Organization child growth standards in the postnatal period

AU - Perumal, Nandita

AU - Ohuma, Eric O.

AU - Prentice, Andrew M.

AU - Shah, Prakesh S.

AU - Al Mahmud, Abdullah

AU - Moore, Sophie E.

AU - Roth, Daniel E.

N1 - Funding Information: There was no specific funding for this study. NP was supported by the Canadian Institutes of Health Research postdoctoral fellowship. The Maternal Vitamin D for Infant Growth trial was funded by the Bill and Melinda Gates Foundation (Grant no. OPP1066764). The Early Nutrition and Immune Development study was supported by the Medical Research Council (UK), through core funding to the MRC International Nutrition Group (MC‐A760‐5QX00) and the UK Department for International Development (DFID) under the MRC/DFID Concordat agreement. Publisher Copyright: © 2022 The Authors. Paediatric and Perinatal Epidemiology published by John Wiley & Sons Ltd.

PY - 2022/11

Y1 - 2022/11

N2 - Background: The INTERGROWTH-21st sex and gestational age (GA) specific newborn size standards (IG-NS) are intended to complement the World Health Organization Child Growth Standards (WHO-GS), which are not GA-specific. We examined the implications of using IG-NS at birth and WHO-GS at postnatal ages in longitudinal epidemiologic studies. Objectives: The aim of this study was to quantify the extent to which standardised measures of newborn size and growth are affected when using WHO-GS versus IG-NS at birth among term-born infants. Methods: Data from two prenatal trials in Bangladesh (n = 755) and The Gambia (n = 522) were used to estimate and compare size at birth and growth from birth to 3 months when using WHO-GS only (‘WHO-GS’) versus IG-NS at birth and WHO-GS postnatally (‘IG-NS’). Mean length-for-age (LAZ), weight-for-age (WAZ) and head circumference-for-age (HCAZ), and the prevalence of undernutrition (stunting: LAZ < −2SD; underweight: WAZ < −2SD; and microcephaly: HCAZ < −2SD) were estimated overall and by GA strata [early-term (370/7–386/7), full-term (390/7–406/7) and late-term (410/7–430/7)]. We used Bland–Altman plots to compare continuous indices and Kappa statistic to compare categorical indicators. Results: At birth, mean LAZ, WAZ and HCAZ, and the prevalence of undernutrition were most similar among newborns between 39 and 40 weeks of GA when using WHO-GS versus IG-NS. However, anthropometric indices were systematically lower among early-term infants and higher among late-term infants when using WHO-GS versus IG-NS. Early-term and late-term infants demonstrated relatively faster and slower growth, respectively, when using WHO-GS versus IG-NS, with the direction and magnitude of differences varying between anthropometric indices. Individual-level differences in attained size and growth, when using WHO-GS versus IG-NS, were greater than 0.2 SD in magnitude for >60% of infants across all anthropometric indices. Conclusions: Using IG-NS at birth with WHO-GS postnatally is acceptable for full-term infants but may give a misleading interpretation of growth trajectories among early- and late-term infants.

AB - Background: The INTERGROWTH-21st sex and gestational age (GA) specific newborn size standards (IG-NS) are intended to complement the World Health Organization Child Growth Standards (WHO-GS), which are not GA-specific. We examined the implications of using IG-NS at birth and WHO-GS at postnatal ages in longitudinal epidemiologic studies. Objectives: The aim of this study was to quantify the extent to which standardised measures of newborn size and growth are affected when using WHO-GS versus IG-NS at birth among term-born infants. Methods: Data from two prenatal trials in Bangladesh (n = 755) and The Gambia (n = 522) were used to estimate and compare size at birth and growth from birth to 3 months when using WHO-GS only (‘WHO-GS’) versus IG-NS at birth and WHO-GS postnatally (‘IG-NS’). Mean length-for-age (LAZ), weight-for-age (WAZ) and head circumference-for-age (HCAZ), and the prevalence of undernutrition (stunting: LAZ < −2SD; underweight: WAZ < −2SD; and microcephaly: HCAZ < −2SD) were estimated overall and by GA strata [early-term (370/7–386/7), full-term (390/7–406/7) and late-term (410/7–430/7)]. We used Bland–Altman plots to compare continuous indices and Kappa statistic to compare categorical indicators. Results: At birth, mean LAZ, WAZ and HCAZ, and the prevalence of undernutrition were most similar among newborns between 39 and 40 weeks of GA when using WHO-GS versus IG-NS. However, anthropometric indices were systematically lower among early-term infants and higher among late-term infants when using WHO-GS versus IG-NS. Early-term and late-term infants demonstrated relatively faster and slower growth, respectively, when using WHO-GS versus IG-NS, with the direction and magnitude of differences varying between anthropometric indices. Individual-level differences in attained size and growth, when using WHO-GS versus IG-NS, were greater than 0.2 SD in magnitude for >60% of infants across all anthropometric indices. Conclusions: Using IG-NS at birth with WHO-GS postnatally is acceptable for full-term infants but may give a misleading interpretation of growth trajectories among early- and late-term infants.

KW - anthropometry

KW - growth

KW - INTERGROWTH-21st newborn size standards

KW - newborn

KW - term-born

KW - World Health Organization child growth standards

UR - http://www.scopus.com/inward/record.url?scp=85132639085&partnerID=8YFLogxK

U2 - 10.1111/ppe.12880

DO - 10.1111/ppe.12880

M3 - Article

C2 - 35570836

AN - SCOPUS:85132639085

SN - 0269-5022

VL - 36

SP - 839

EP - 850

JO - Paediatric and Perinatal Epidemiology

JF - Paediatric and Perinatal Epidemiology

IS - 6

ER -