Effects of weekly iron supplementation on pregnant Indonesian women are similar to those of daily supplementation

The effect of daily rather than weekly iron supplementation was compared in women who were 8-24 wk pregnant. One group (n = 68) received 60 mg Fe/d, the second group (n = 71) received 120 mg Fe/wk, given at once. Supplementation lasted 11.3 wk on average, depending on gestational date at entry, and was not supervised. Hemoglobin increased in both groups (P < 0.001); serum ferritin did not change significantly. There was no significant difference between groups for changes in hemoglobin and serum ferritin. In a subgroup of women with a hemoglobin concentration < 110 g/L at baseline (n = 45 daily; n = 54 weekly) no significant within-group changes occurred in serum ferritin, but the change in the daily group was 4.1 micrograms/L higher than in the weekly group (P = 0.049). Compliance, as indicated by two positive stool tests, was approximately equal to 54.3% in the daily group and 62.2% in the weekly group. We conclude that for the complete sample of subjects, the treatment effect of daily compared with weekly supplementation was similar under conditions resembling a normal antenatal care program.