Iron, Folate, and B12 Deficiencies and their Associations with Anemia among Women of Childbearing Age in a Rural Area in Northern China

Abstract

Objective: To assess the prevalence of folate, vitamin B12, and iron deficiencies and their associations with anemia among women of childbearing age in northern China, an area with a reported high incidence of neural tube defects. Methods: Plasma folate, vitamin B12, ferritin, and hemoglobin levels were measured among 1,671 non-pregnant women of childbearing age from Xianghe County, Hebei Province, China in June 2004. Results: Geometric means [95 % confidence interval (CI)] of plasma concentrations were 9.3 (4.0, 21.6) nmol/L for folate, 213.1 (82.4, 550.9) pmol/L for vitamin B12, 17.4 (1.1, 278.6) µg/L for ferritin, and 129.9 (104.6, 161.4) g/L for hemoglobin (Hb). Approximately 24 % of women had biochemical evidence of folate deficiency (<6.8 nmol/L), 21.4 % were deficient (<148 pmol/L) in vitamin B12, 30.2 % had iron depletion (<15 μg/L), and anemia (Hb < 120 g/L) was detected among 15.4 % of women. Of the three nutrients, only iron depletion (ferritin < 15 μg/L) was independently associated with anemia (adjusted odds ratio = 6.4, 95 % CI 4.8, 8.6). Conclusions: Although there were substantial proportions of folate and vitamin B12 deficiencies among women of childbearing age in northern China, iron deficiency was the most important contributor to anemia.