Background:Iron supplementation during pregnancy in programmatic settings has failed to produce desired results. Formulation of iron supplementation may have a role in compliance and hematological parameters.Objective:We did this study to compare the compliance to iron supplementation, change in mean hemoglobin and serum ferritin level after iron supplementation in capsule form and tablet form during pregnancy.Materials and Methods:In this single-blinded (investigator blinded), active comparator, randomized controlled trial we enrolled pregnant women (aged ≥18 years) from May to November 2014 during second trimester to receive iron supplementation either as capsule (ferrous fumarate) or tablet (ferrous sulphate) during entire pregnancy. The outcome was compliance (good compliance ≥ 90%) to iron supplementation assessed by pill count and change in mean hemoglobin and serum ferritin. Statistical significance was tested using Chi-square test and Student's t test.Results:We enrolled and randomized 204 pregnant women for iron supplementation; capsule form (n = 100) and tablet form (n = 104). Out of which 52 (25.5%) women (23 in capsule arm and 29 in tablet arm) were lost to follow up. As compared to tablet arm, the capsule arm had higher good compliance (22% vs 16.8%), increase in mean hemoglobin (0.79 vs 0.44 gm/dL) and increase in mean serum ferritin (2.50 vs -2.14 ng/mL), but the difference was not statistically significant.Conclusion:Pregnant women who received either of the formulation reported a low compliance. Iron supplementation in capsule formulation resulted in more increase in blood hemoglobin level, though clinically insignificant.