Rapid recovery of fat mass in small for gestational age preterm infants after term
Paola Roggero1, Maria L Giannì, Nadia Liotto
1Neonatal Intensive Care Unit, Department of Mother and Infant Science, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy. paola.roggero@unimi.it
Insights
Preterm infants born small for gestational age (SGA) catch up in fat stores quickly, regardless of birth weight. However, their overall weight gain may lag. Further research is needed on metabolic effects.
Area of Science:
- Neonatal research
- Pediatric endocrinology
- Growth and development
Background:
- Preterm infants, especially those small for gestational age (SGA), are at risk for increased adiposity.
- Rapid postnatal weight gain in these infants may exacerbate adiposity.
- Limited data exists on early-life dynamic changes in body weight and fat mass (FM) in preterm infants.
Purpose of the Study:
- To investigate early postnatal weight and fat mass (FM) gain in preterm infants.
- To compare anthropometric trajectories based on fetal growth patterns.
Main Methods:
- Prospective monitoring of growth parameters and FM in 195 preterm infants (birth weight ≤1500 g).
- Infants categorized as adequate for gestational age (AGA) with or without growth retardation (GR-/GR+), and SGA.
- Weight and FM assessed using air displacement plethysmography.
Main Results:
- At five months, SGA infants had significantly lower weight z-scores compared to AGA infants.
- At term, AGA (GR+) and SGA infants had lower FM than AGA (GR-) infants.
- In the first three months, FM gain was comparable between AGA (GR+) and SGA groups, and higher than in AGA (GR-) infants. FM was similar across all groups at three months.
Conclusions:
- Fetal growth patterns influence anthropometric catch-up potential in preterm infants.
- Fat mass restoration appears to occur irrespective of birth weight in early infancy.
- Metabolic implications of these growth dynamics require further investigation.
Background:
Preterm small for gestational age (SGA) infants may be at risk for increased adiposity, especially when experiencing rapid postnatal weight gain. Data on the dynamic features of body weight and fat mass (FM) gain that occurs early in life is scarce. We investigated the postnatal weight and FM gain during the first five months after term in a cohort of preterm infants.
Methodology/Principal Findings:
Changes in growth parameters and FM were prospectively monitored in 195 infants with birth weight ≤1500 g. The infants were categorized as born adequate for gestational age (AGA) without growth retardation at term (GR-), born AGA with growth retardation at term (GR+), born SGA. Weight and FM were assessed by an air displacement plethysmography system. At five months, weight z-score was comparable between the AGA (GR+) and the AGA (GR-), whereas the SGA showed a significantly lower weight.The mean weight (g) differences (95% CI) between SGA and AGA (GR-) and between SGA and AGA (GR+) infants at 5 months were -613 (-1215; -12) and -573 (-1227; -79), respectively. At term, the AGA (GR+) and the SGA groups showed a significantly lower FM than the AGA (GR-) group. In the first three months, change in FM was comparable between the AGA (GR+) and the SGA groups and significantly higher than that of the AGA (GR-) group.The mean difference (95% CI) in FM change between SGA and AGA (GR-) and between AGA (GR+) and AGA (GR-) from term to 3 months were 38.6 (12; 65); and 37.7 (10; 65). At three months, the FM was similar in all groups.
Conclusions:
Our data suggests that fetal growth pattern influences the potential to rapidly correct anthropometry whereas the restoration of fat stores takes place irrespective of birth weight. The metabolic consequences of these findings need to be elucidated.
