Prophylactic iron supplementation for the prevention of iron deficiency and anemia in infants born at 34 weeks of gestation or later at 4-6 months of age: A prospective cohort study

Abstract

Background: Iron deficiency anemia (IDA) typically manifests in infants after six months of age, particularly among those exclusively breastfed, as endogenous iron stores begin to deplete from the fourth month of age. If left unaddressed by the six-month screening, IDA can lead to long-term developmental repercussions. Early prophylactic intervention is therefore critical for prevention.

Objective: To study the prevalence of IDA (hemoglobin and serum ferritin) at six months between infants receiving prophylactic iron supplementation from 4–6 months and those who did not.      

Methodology: A prospective cohort study was conducted involving 185 healthy infants (gestational age>34 weeks) attending the Well-Baby Clinic at Lampang Hospital. Participants were divided into two groups: group 1 (n=81) received daily prophylactic iron 1 mg/kg/dose everyday supplementation from age 4 to 6 months, while group 2 (n=104) received no supplementation. Nutritional status, weight, and hematological parameters including Complete Blood Count (CBC), serum ferritin, and reticulocyte count (RC) were evaluated for both groups, and the prevalence of anemia at the six-month of age was determined.

Results: The overall incidence of IDA (hemoglobin <11 g/dL) among the participants was 30.2% (56/185). The prevalence of supplemented group was lower than in the non-supplemented group (24.7% vs 34.6%), although the adjusted association was not statistically significant (adjusted risk ratio [aRR], 0.79; 95% CI, 0.49-1.27; p value 0.334). Iron deficiency (serum ferritin <12 ng/mL) occurred in 11.1% of supplemented infants and 21.2% of non-supplemented infants. After adjustment for birth weight, gestational age, sex, and exclusive breastfeeding, prophylactic iron was associated with a lower risk of iron deficiency (aRR, 0.50; 95% CI, 0.25-0.98; adjusted odds ratio, 0.37; 95% CI, 0.14-0.97; p value 0.044). The supplemented group also had a higher adjusted mean ferritin concentration (mean difference, 18.18 ng/mL; 95% CI, 4.30-32.07; p value 0.011) and hematocrit (mean difference, 0.77 percentage points; 95% CI, 0.02-1.53; p value 0.044). Adjusted differences in hemoglobin and other red-cell indices were not statistically significant.

Conclusion: Prophylactic oral iron supplementation at a dose of 1 mg/kg/day, initiated at 4 months of age in >34 week and term infants, significantly increase serum ferritin levels without evidence of iron overload. Supplementary as a preventive strategy against iron deficiency in young infants in Lampang Province, particularly before receive complementary foods.