The influence of iron, vitamin B 12, and folate levels on soluble transferrin receptor concentration in pregnant women

Abstract

Background: Soluble transferrin receptor (sTfR) concentration is high in iron deficiency and in conditions of increased erythropoiesis. In developing countries like Brazil, pregnant women usually have concurrent iron, vitamin B 12, and folate deficiencies. This study investigated the relationship between serum sTfR concentration and iron, vitamin B 12, and folate status in pregnant women. Methods: The concentration of the sTfR, hematocrit (Hct), hemoglobin (Hb), red blood cell (RBC) and white blood cell (WBC) counts, serum iron (SI), total iron-binding capacity (TIBC), transferrin saturation, serum ferritin, zinc protoporphyrin (ZPP), vitamin B 12, and serum and RBC folate were determined in 40 healthy pregnant women who delivered term babies. Results: sTfR concentration was significantly higher when the women had iron deficiency (serum ferritin <10 μg/l, p<0.01), but there was no significant difference in sTfR concentration according to vitamin B 12, serum, and RBC folate concentrations. Women who had serum ferritin <10 μg/l also had lower vitamin B 12 values ( p<0.01). There was no significant correlation between vitamin B 12 and serum folate with sTfR concentration. According to a regression analysis, sTfR concentration was associated with serum iron, serum ferritin, RBC count, and hemoglobin concentration. Conclusion: Iron was the only micronutrient that influenced the sTfR concentration. Vitamin B 12 and folate concentrations were probably not sufficiently low to have an impact on the sTfR concentration.