Defining Iron Deficiency Anaemia in Pregnancy: the Diagnostic Role of Serum Iron Indicators and C-reactive Protein

ABSTRACT

Background: Definition of iron deficiency anaemia could be problematic in areas where iron deficiency co-exists with infection. Aim: This study was aimed at providing the prevalence of anaemia in pregnancy in Port Harcourt and to examine the diagnostic role of serum iron indicators and C- reactive protein in defining iron deficiency anaemia. Methods: Iron status indicators; serum iron; TIBC; percentage transferrin saturation; serum ferritin; haemoglobin concentration and C-reactive protein were assessed in 1;371 pregnant women and 60 age-matched non-pregnant controls using standard colorimetric; immunoassay and serologic procedures. Results: Iron deficiency anaemia was present in 5of our apparently healthy non-pregnant women and in 8.9of the pregnant women. Iron deficiency (ferritin 12 ng/ml) accounted for 15of anaemia in the control group and 18.0of anaemia in the pregnant women. Elevated C-reactive protein (20 mg/l) was found to be common with the anaemic pregnant women (40.2) compared with 6.7among non-pregnant control group (p0.0001). The Hb; serum iron; TIBC;transferrin saturation and serum ferritin levels in anaemic pregnant women were found to be significantly lower than the non-pregnant control group (p0.0001) while the C-reactive protein level in the anaemic pregnant women was significantly higher than the non-pregnant control group (p0.0001). Conclusion: The prevalence of iron deficiency anaemia among apparently pregnant women in this locality is high. Part of the contributory factor may be infection or inflammation; hence; ferritin alone may not reliably define anaemia in pregnancy. A combination of haemoglobin concentration; transferrin saturation and serum ferritin concentration should form a regular practice in order to assist in reducing the incidence of anaemia in pregnancy