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Postnatal growth retardation: a universal problem in preterm infants.
R J Cooke1, S B Ainsworth, A C Fenton
1Special Care Baby Unit, Royal Victoria Infirmary, University of Newcastle upon Tyne, UK. rcooke@utmem.edu
Postnatal growth retardation (PGR) is common in preterm infants across all neonatal care levels. Significant variability exists in growth outcomes and hospital stay duration between and within units, highlighting nutritional support concerns.
Area of Science:
- Neonatalogy
- Pediatric Growth and Development
- Clinical Nutrition
Background:
- Previous research indicated inevitable postnatal growth retardation (PGR) in preterm infants from a single level III neonatal intensive care unit.
- The generalizability of these findings to other neonatal care settings (level III, I-II) was uncertain.
Purpose of the Study:
- To evaluate postnatal hospital growth in preterm infants.
- To compare growth outcomes for preterm infants discharged from level III tertiary care units and level I-II special care baby units.
Main Methods:
- Study included preterm infants (gestation ≤ 32 weeks; weight ≤ 1500 g) surviving to discharge.
- Infant weight was recorded at birth and discharge, with z scores calculated using British Foundation Growth Standards.
- Postnatal growth retardation (PGR) was determined by subtracting birth z score from discharge z score; data analyzed using split plot and stepwise regression.
Main Results:
- No significant differences in birth characteristics, illness severity (CRIB score), hospital stay, weight gain, or PGR were found between level III and level I-II units.
- Substantial variation in hospital stay, weight gain, discharge weight, and PGR degree was observed between individual level III units.
- Even greater variability in these parameters was noted between individual level I-II units.
Conclusions:
- Postnatal growth retardation (PGR) is a universal yet variable challenge for preterm infants discharged from both level III and I-II neonatal units.
- The significant variability in growth outcomes underscores critical questions regarding the adequacy of nutritional support provided to preterm infants during and after hospitalization.
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