Increased lipid peroxidation in pregnant women after iron and vitamin C supplementation

Iron overload could promote the generation of free radicals and result in d eleterious cellular damages. A physiological increase of oxidative stress h as been observed in pregnancy. A routine iron supplement, especially a comb ined iron and vitamin C supplementation, without biological justifications (low hemoglobin [Hb] and iron stores) could therefore aggravate this oxidat ive risk. We investigated the effect of a daily combined iron supplementati on (100 mg/d as fumarate) and vitamin C (500 mg/d as ascorbate) for the thi rd trimester of pregnancy on lipid peroxidation (plasma TBARS), antioxidant micronutriments (Zn, Se, retinol, vitaminE, (beta -carotene) and antioxida nt metalloenzymes (RBC Cu-Zn SOD and Se-GPX). The iron-supplemented group ( n = 27) was compared to a control group (n = 27), age and number of pregnan cies matched. At delivery, all the women exhibited normal Hb and ferritin v alues. In the supplemented group, plasma iron level was higher than in the control group (26.90 +/- 5.52 mmol/L) and TBARs plasma levels were signific antly enhanced (p < 0.05) (3.62 +/- 0.36 vs 3.01 +/- 0.37 mmol/L). No signi ficant changes were observed in plasma trace elements and red blood cell an tioxidant metalloenzymes. Furthermore, the (x-tocopherol plasma level was l owered in the iron-supplemented groups, suggesting an increased utilization of vitamin E. These data show that pharmalogical doses of iron, associated with high vita min C intakes, can result in uncontrolled lipid peroxidation. This is predi ctive of adverse effects for the mother and the fetus. This study illustrat es the potential harmful effects of iron supplementation when prescribed on ly on the assumption of anemia and not on the bases of biological criteria.