Presented at the Neonatal Society 2006 Widdowson Meeting.
Hay G1, Refsum H1, Melbye EL1, Whitelaw A2, Haug E1, Borch-Iohnsen B1
1 Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, Oslo, Norway
2 Clinical Science, University of Bristol, Bristol, UK
Background: Adequate iron status during pregnancy and infancy is essential for optimal development and growth in children.
Objective: To examine cord serum ferritin (SF) and cord transferrin receptor (TfR) in healthy newborns, to identify determinants for iron indices at birth and their impact on iron status throughout the first two years of life.
Methods: 363 healthy term infants and their mothers were recruited. SF and TfR were measured at birth, 6, 12, 18 and 24 months. Smoking and use of nutritional supplements during pregnancy were documented by questionnaire. The study was approved by the Oslo Regional Committee for Research Ethics.
Results: Geometric mean (95% CI) for cord SF was 159 (148-171) μg/L, and for cord TfR 7.3 (7.0- 7.6) mg/L. There was a negative correlation between SF and TfR, r = -0.21, P < 0.001. Cord SF was associated negatively with smoking in pregnancy and male gender and positively associated with iron intake in the 2nd trimester. Cord TfR had positive associations with gestational age, male gender and pre-pregnancy weight. Cord SF was correlated with SF at 6, 12 and 24 months. Boys had higher TfR at birth and lower SF at 6 months: There was a striking association between quartiles for cord SF and the proportion with SF<15 μg/L at 6 months (boys) and at 12 months (both genders).
Conclusions: Cessation of smoking and adequate iron prophylaxis in pregnancy may improve iron status in infancy. Cord SF is a strong predictor of iron status during the first year. Boys have an increased risk of iron deficiency in early infancy.
References
Tamura T, Goldenberg RL, Hou J, et al. Cord serum ferritin concentrations and mental and psychomotor development of children at five years of age. J Pediatr 2002;140:165-70.
Sweet DG, Savage GA, Tubman R, Lappin TR, Halliday HL. Cord blood transferrin receptors to assess fetal iron status. Arch Dis Child Fetal Neonatal Ed 2001;85:F46-8.