RESUMO
OBJECTIVE: Iron supplementation was found to be a cause of oxidative stress. The aim of this study was to compare oxidative stress in pregnancies with and without iron supplementation in the first trimester pregnancies. METHODS: One hundred and eight women in the first trimester of normal pregnancies were randomly assigned to three groups. Patients were grouped as following: Group 1 received placebo (n = 36), group 2 received folate supplementation (n = 36) and group 3 was directed to the iron supplementation (n = 36). Oxidative stress was assessed at 14th week of gestation by the utilization of serum γ-glutamyl transferase level. Pregnancies were followed until delivery. Relationship between the oxidative stress and pregnancy outcome was assessed among groups. RESULTS: Mean age was similar among groups, mean gravidity and parity were significantly lower in group with Fe supplementation (p < 0.05). Maternal weight and weight gain during pregnancy were also significantly lower in group 3 (p < 0.05). Mean serum albumin levels were similar among groups while serum γ-glutamyl transferase (GGT) levels were significantly higher in group 3. There were 10 cases of oligohydramnios in group 3, two cases in group 2 and no cases in group 1 (p < 0.001). CONCLUSION: Iron supplementation during first trimester pregnancy was found to be associated with an increased oxidative stress.