{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T12:19:10Z","timestamp":1790079550587,"version":"4.0.1"},"reference-count":38,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,16]],"date-time":"2022-12-16T00:00:00Z","timestamp":1671148800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>This retrospective cohort study aims to determine the epidemiology of iron deficiency among extreme preterm neonates and the association of iron-deficient status during the NICU stay with neurodevelopmental outcomes at 18\u201324 months. Neonates \u226429 weeks gestational age (GA) born between June 2016 and December 2019, who received routine iron supplementation were enrolled. Iron deficiency was defined as reticulocyte\u2013hemoglobin (Ret-Hb) levels \u2264 29 pg at 36 weeks corrected age. A subcohort of neonates completed standardized developmental assessment at 18\u201324 months corrected age. Significant neurodevelopmental impairment (sNDI) was defined as either Bayley Scales of Infant Development score &lt; 70 or cerebral palsy or blindness or hearing aided. Among a cohort of 215 neonates [GA 25.8 (1.7) weeks, birthweight 885 (232) g], prevalence of iron deficiency was 55%, 21%, 26%, and 13%, in neonates &lt;24 weeks, 24\u201325 + 6 weeks, 26\u201327 + 6 weeks, and \u2265 28 weeks GA, respectively. Male sex and receipt of corticosteroid therapy were associated with iron-deficiency. In the subcohort analysis (n = 69), there was no statistically significant association between Ret-Hb levels at 36 weeks corrected age and the risk of sNDI [OR 0.99 (95% CI 0.85\u20131.2)]. Male infants and those who received postnatal corticosteroids are likely to have iron-limited erythropoiesis at corrected term despite routine iron-supplementation; however, low Ret-Hb levels during the neonatal period were not associated with significant neurological disability in early childhood.<\/jats:p>","DOI":"10.3390\/nu14245343","type":"journal-article","created":{"date-parts":[[2022,12,16]],"date-time":"2022-12-16T02:54:02Z","timestamp":1671159242000},"page":"5343","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Prevalence and Implications of Low Reticulocyte\u2013Hemoglobin Levels among Extreme Preterm Neonates: A Single-Center Retrospective Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5182-1840","authenticated-orcid":false,"given":"Jhanahan","family":"Sriranjan","sequence":"first","affiliation":[{"name":"Department of Pediatrics, McMaster University, Hamilton, ON L8S 3L8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine","family":"Kalata","sequence":"additional","affiliation":[{"name":"Registered Dietitian, McMaster Children\u2019s Hospital, Hamilton, ON L8N 3Z5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4026-3211","authenticated-orcid":false,"given":"Gerhard","family":"Fusch","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, McMaster University, Hamilton, ON L8S 3L8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Thomas","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, McMaster University, Hamilton, ON L8S 3L8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ipsita","family":"Goswami","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, McMaster University, Hamilton, ON L8S 3L8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/S0304-419X(02)00068-9","article-title":"The role of iron in cell cycle progression and the proliferation of neoplastic cells","volume":"1603","author":"Le","year":"2002","journal-title":"Biochim. 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