Side Effects of Daily versus Weekly Iron Supplementation in Pregnant Women

Abstract

Background & Objective: Iron supplementation in pregnant women is highly recommended, however there is reduced compliance due to the common gastrointestinal side effects. This study aimed to compare the clinical side effects between pregnant women with daily and weekly iron supplementation. Methods: Seventy-nine pregnant women who met the inclusion and exclusion criteria were given iron supplements every day (group 1, n = 37) and twice a week (group 2, n = 42). All numerical data were assessed by independent t-test. Side effects were assessed after one month of administration using a questionnaire containing complaints felt by pregnant women and were evaluated by chi-square test using SPSS 25. A P value < 0.05 was considered as statistically significant. Results: The most common side effects of iron supplementation in both groups were black feces (35.4%) and nausea (31.6%). Nausea (45.9% vs. 19.0%; P < 0.05) and constipation (35.1% vs. 11.9%; P < 0.05) were more frequent in group 1 than in group 2, respectively. Other side effects, such as heartburn, flatulence, vomiting, black feces, and urine discoloration did not differ significantly between the two groups (P > 0.05). Conclusion: The daily iron supplementation elevated the episodes of nausea and constipation during pregnancy than the weekly supplementation. The daily iron supplementation in pregnant women increases the risk of side effects, potentially reducing compliance.