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Published on: May 10, 2022
Iron retention in preterm infants fed low iron intakes: a metabolic balance study
1Department of Pediatrics, University of California-Davis, 2516 Stockton Blvd., Sacramento, CA 95817, USA. ijgriffin@ucdavis.edu
Insights
Iron retention in preterm infants is adequate with intakes around 1 mg/kg/day, despite being lower than recommended. Studies show iron retention increases over time and supports growth needs.
Area of Science:
- Neonatal Nutrition
- Pediatric Gastroenterology
- Mineral Metabolism
Background:
- Limited data exists on iron retention in healthy preterm infants.
- Current recommendations for iron intake in preterm infants are higher than typically provided.
Purpose of the Study:
- To investigate iron retention in preterm infants.
- To assess iron requirements for growth and red cell mass expansion.
Main Methods:
- Conducted 24 metabolic balance studies in 13 preterm infants (17-63 days old).
- Administered an iron intake of 1.11 mg/kg/day.
- Performed balance studies 7 days apart in 11 infants.
Main Results:
- Iron retention was positive in most infants, increasing significantly between initial and subsequent balance studies.
- Iron retention was positively correlated with the duration of enteral feeding.
- Observed iron retention exceeded estimated requirements for growth and red cell mass expansion.
Conclusions:
- Iron intakes of approximately 1 mg/kg/day appear sufficient for preterm infant growth during this period.
- This intake is lower than the estimated fetal accretion rate.
- Further research may refine optimal iron supplementation strategies for preterm infants.
Abstract:
There is little data on iron retention in healthy preterm infants. Twenty-four metabolic balance studies were carried out in 13 preterm infants between 17 and 63 days of age, in 11 cases 2 balance were carried out 7d apart. Iron intake was 1.11 mg/kg/day (SD 0.06), less than the 2 mg/kg/d typically recommended for preterm infants. Iron retention was positive in the majority (3/13) of the first balances, and in all 11 of the second balances. Iron retention increased significantly between the two balances (from 0.095 mg/kg/d (SD 0.178) to 0.270 (SD 0.209)). Iron retention was significantly related to the time that the infant had been on enteral feeds at the time the balance was carried out. Iron retention was significantly greater than the requirement estimated to be needed to meet the needs for growth and expansion of the circulating red cell mass. Iron intakes of about 1mg/kg/d seem to be adequate to support the requirements for growth in preterm infants during this time period, but are significantly less than the estimated in utero accretion rate of the fetus.
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