Postnatal Growth Failure and Z-Score

  • Haydi Al-Wassia
  • Prakesh S. Shah


Advances in neonatal intensive care have resulted in remarkable improvements in the survival of the sickest and extremely premature newborn infants. However, this has resulted in an increase in morbidities and significant impact on long-term neurodevelopmental outcomes. Optimizing, monitoring and achieving nutritional adequacy and growth of this group of infants remain significant challenges during their course in neonatal intensive care units. Postnatal growth failure is extremely common in these infants. Several studies have reported the negative effect of suboptimal growth on long-term neurodevelopmental outcomes. Despite this, there is a lack of uniformity among neonatologists with regard to the best method of assessing growth of the preterm infant and the best definition of postnatal growth failure. Various methods used to assess growth of preterm infants during their NICU stay and during infantile and childhood periods are discussed in this chapter. Methods using standardized scores such as z-score have the advantage of individualizing a growth chart and monitor growth of an individual child with reference to his/her own growth potential and at the same time with reference to population standards. Z-scores also have the advantage of accommodating extreme values of growth. Emerging evidence indicates that z-score is moderately correlated with neurodevelopmental outcome in childhood whereas other measures have failed to achieve significance. In this chapter, we review available evidence regarding utility of z-scores in monitoring postnatal growth.


Preterm Infant Neonatal Intensive Care Unit Postnatal Growth Growth Chart Neurodevelopmental Outcome 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



American Academy of Paediatrics


Appropriate for gestational age


Birth weight


Center for Disease Control


Canadian Paediatric Society


Extremely low birth weight


Full term


Gestational age


Infant Health and Development Program


National Institute of Child Health and Human Development


Neonatal intensive care unit


Odds ratio


Postnatal growth failure




Systolic blood pressure


Standard deviation


Small for gestational age


Very low birth weight


World Health Organization


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of PediatricsMount Sinai Hospital, University of TorontoTorontoCanada
  2. 2.Department of Health Policy, Management and EvaluationUniversity of TorontoTorontoCanada

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