Am J Perinatol
DOI: 10.1055/a-2200-3285
Original Article

Iron Deficiency Prior to Discharge in Very Low Birth Weight Infants: Screening with Reticulocyte Hemoglobin Content

1   Division of Neonatology, Department of Pediatrics, Thomas Jefferson University Hospital/Nemours Children's Health, Philadelphia, Pennsylvania
Faraz Afridi
2   Division of Neonatology, Department of Pediatrics, Cooper University Hospital, Camden, New Jersey
Dana Neumann
1   Division of Neonatology, Department of Pediatrics, Thomas Jefferson University Hospital/Nemours Children's Health, Philadelphia, Pennsylvania
Barbara Amendolia
2   Division of Neonatology, Department of Pediatrics, Cooper University Hospital, Camden, New Jersey
Nicole Kilic
2   Division of Neonatology, Department of Pediatrics, Cooper University Hospital, Camden, New Jersey
Vishwanath Bhat
2   Division of Neonatology, Department of Pediatrics, Cooper University Hospital, Camden, New Jersey
Vineet Bhandari
2   Division of Neonatology, Department of Pediatrics, Cooper University Hospital, Camden, New Jersey
1   Division of Neonatology, Department of Pediatrics, Thomas Jefferson University Hospital/Nemours Children's Health, Philadelphia, Pennsylvania
› Author Affiliations
Funding None.


Objective This study aimed to assess the iron status prior to discharge in very low birth weight (VLBW) infants utilizing reticulocyte hemoglobin content (CHr) and evaluate the impact of delayed cord clamping (DCC) on iron status.

Study Design This is a retrospective analysis of VLBW infants from two tertiary level of care Neonatal Intensive Care Units. The primary outcome was the proportion of VLBW infants with low CHr (<29 pg) prior to discharge. Hematologic parameters were also compared between infants who received or did not receive DCC. Infants with a positive newborn screen for hemoglobin Bart's were excluded.

Results Among the 315 infants included, 99 infants (31.4%) had low CHr prior to discharge. The median (interquartile range) CHr prior to discharge was 30.8 pg (28.4–39 pg). DCC was performed in 46.7% of infants. Hemoglobin at birth, discharge, and CHr prior to discharge were higher and the need for blood transfusion and the number of infants with low CHr prior to discharge were lower in the DCC group.

Conclusion Approximately 31.4% of VLBW infants had low CHr near the time of discharge suggesting they were iron deficient. DCC improved hematological parameters prior to discharge in VLBW infants. CHr content can be used to guide iron supplementation in VLBW infants to potentially improve their iron status and long-term neurocognitive outcomes.

Key Points

  • DCC was associated with an improved hemoglobin and iron status at discharge in VLBW infants.

  • CHr is an early and reliable marker for iron deficiency.

  • Approximately one in three VLBW infants can be iron deficient at the time of discharge.


Presented at the Eastern Society of Pediatric Research, 2022 and Pediatric Academic Societies Meeting, 2022.

Authors' Contributions

Geetika Kennady MD conceptualized and designed the study, performed data collection, interpreted results, and drafted and revised the manuscript.

Faraz Afridi MD, Dana Neumann DO, Barbara Amendolia DrNP, Nicole Kilic MSN performed data collection and reviewed the manuscript.

Vishwanath Bhat MD, Vineet Bhandari MD critically reviewed the data analysis, critically reviewed and revised the manuscript.

Zubair H. Aghai MD conceptualized and designed the study, performed data analysis, and interpreted the results.

Supplementary Material

Publication History

Received: 09 June 2023

Accepted: 25 October 2023

Accepted Manuscript online:
27 October 2023

Article published online:
28 November 2023

© 2023. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
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