Objective: This study was designed to determine the favorable effects of received multivitamin versus multivitamin-mineral supplements on metabolic profiles and biomarkers of oxidative stress among Iranian pregnant women.Methods: This double-blind randomized-controlled clinical trial was conducted among 70 pregnant women, primigravida, aged 18-35 years old between 16 and 37 weeks gestation. Subjects were randomly assigned to receive either the multivitamin (n = 35) or multivitamin-mineral supplements (n = 35) for 20 weeks. Fasting blood samples were taken at baseline and after a 20-week intervention to measure lipid profiles and biomarkers of oxidative stress.Results: After 20 weeks of intervention, multivitamin-mineral supplementation resulted in a significant difference on serum triglycerides levels (changes from baseline in multivitamin-mineral group: +6.1 versus in multivitamin group: +45.9 mg/dl, p = 0.04) compared with the multivitamin group. In addition, increased concentrations of serum HDL-cholesterol (changes from baseline in multivitamin-mineral group: +0.1 versus in multivitamin group: -7.4 mg/dl, p = 0.02) and total glutathione (GSH) levels (changes from baseline in multivitamin-mineral group: +151.09 versus in multivitamin group: -116.21 µmol/l, p = 0.003) were also seen in the multivitamin-mineral group compared with the multivitamin group.Conclusion: Supplementation of multivitamin-mineral compared to multivitamin supplementation for 20 weeks during pregnancy had beneficial effects on triglycerides, HDL-cholesterol and GSH levels. [ABSTRACT FROM AUTHOR]