Neonatal Iron Stores Depend on Gestational Age: A Prospective Comparative Cross-sectional Study at Neonatal Intensive Care Unit, University of Nigeria Teaching Hospital, Enugu State, Nigeria

Aims: To establish mean values for serum ferritin at different gestational ages. To determine the relationship between serum ferritin and gestational age. Methodology: This was a prospective, comparative, cross sectional study carried out at the Neonatal Intensive Care Unit of the University of Nigeria Teaching Hospital (UNTH), Enugu State, Nigeria between June and December 2014. The study included 140 newborns with gestational ages of 25 weeks to 39 weeks, delivered at the UNTH. Babies with C-reactive protein levels > 10mg/dl, who were intra-uterine growth restricted, and whose mothers had conditions associated with low iron stores were excluded from the study. Anthropometric measurements were recorded for all subjects. Serum ferritin was measured at birth and this was correlated with gestational age. Results: Serum ferritin levels ranged from 20.6 to 296.4µg/l. The mean serum ferritin level was 93.14µg/l ± 57.69. There was a significant difference among the mean serum ferritin levels amongst different categories of gestational age (F = 11.159, P <.001).  Low serum ferritin was found in 85.7%, 48.1% and 16.7% of extreme preterms, very preterms and moderate to late preterms respectively 2 = 49.777, P < .05). Extreme preterms were sixty-four times more likely than term babies to have low serum ferritin (P <.01, OR = 64.00, 95% C.I for OR = 6.570 – 623.455), while very preterms were ten times more likely than term babies to have low serum ferritin levels (P < .001, OR = 9.905 95% C.I = 3.209 -30.570). In addition, moderate to late preterms were two times more likely than term babies to have low serum ferritin levels (P = 0.220, OR = 2.133, 95% C.I for OR = 0.635 – 7.167). There was a significant strong positive correlation between serum ferritin levels and gestational age in the study population (r = 0.656, P < .001). Conclusion: There is a wide range of serum ferritin amongst newborn babies. There is also a significant strong positive correlation between serum ferritin levels and gestational age.