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Published on: June 29, 2013
Delay of catch-up growth in very low birthweight infants
1Department of Paediatrics, National Women's Hospital, Epsom, Auckland.
Insights
Appropriate for gestational age, very low birth weight infants show catch-up growth. Healthy infants reach birth weight percentiles by three months, while those with neonatal illness experience delayed recovery.
Area of Science:
- Neonatalogy
- Pediatric Growth and Development
Background:
- Very low birth weight (VLBW) infants often experience growth challenges.
- Assessing catch-up growth is crucial for VLBW infant outcomes.
Purpose of the Study:
- To evaluate catch-up growth in appropriate for gestational age (AGA) VLBW infants.
- To compare growth trajectories between healthy and unwell VLBW infants.
Main Methods:
- Retrospective review of 74 AGA VLBW infants' anthropometric data.
- Calculation of Z-scores for weight, length, and head circumference.
- Comparison of growth between "well" and "unwell" infants (defined by specific morbidities).
Main Results:
- All VLBW infants exhibited reduced Z-scores at one week, persisting to 35 weeks postmenstrual age.
- Healthy infants regained birth Z-scores by three months post-term.
- Infants with neonatal illness showed significantly lower weight and length Z-scores at three months.
Conclusions:
- AGA VLBW infants who are healthy achieve their birth percentiles by three months post-term.
- Significant neonatal illness delays catch-up growth recovery in VLBW infants.
Aim:
To determine if appropriate for gestational age, very low birth weight infants demonstrate catch-up growth.
Methods:
The notes of 74 appropriate for gestational age, very low birth weight infants were reviewed and anthropometric measures converted into standard deviation scores (Z-scores). The growth of "well" infants was compared with that of "unwell" infants (those who developed necrotising enterocolitis, bronchopulmonary dysplasia or were not feeding at one week of age).
Results:
All infants showed reduced weight (p<0.001) and head circumference (p<0.01) Z-scores at one week of age. This persisted until 35 weeks postmenstrual age in both groups, by which time length Z-scores had also reduced. The well group had regained birth Z-scores for all measurements by three months post-term. However the unwell group still had significantly lower weight (p<0.01) and length (p<0.05) Z-scores at three months.
Conclusions:
Well very low birth weight infants regained their birth percentiles by three months post-term. In infants with significant neonatal illness, this recovery was delayed.
