Intermittent oral iron supplementation during pregnancy.

RATIONALE It has been suggested that in pregnant women weekly iron supplements are as effective as daily supplements in preventing iron deficiency anaemia (IDA). OBJECTIVE To compare the effectiveness of prophylactic antenatal oral iron supplements given weekly, thrice weekly and daily in preventing IDA in pregnancy. DESIGN A randomised control trial. SETTING University antenatal clinic, (UANC) Galle. SUBJECTS AND METHOD An oral iron supplement containing 100 mg of elemental iron was randomly given weekly (n = 26) thrice weekly (n = 35) and daily (n = 31) to 92 women who were 14 to 24 weeks pregnant. Haemoglobin (Hb), serum ferritin (SF) and haematocrit (Hct) were assessed before and after 12 to 20 weeks of supplementation and a logistic regression analysis carried out. RESULTS The risk of developing anaemia was significantly higher in the weekly (odds ratio 15, 95% CI 1.4-165.6, p < 0.03) and possibly higher in the thrice weekly (odds ratio 3, 95% CI 0.3-30.3, p = 0.3) groups. The risk of developing iron deficiency (SF < 12 micrograms/l) was also significantly higher in the weekly (odds ratio 18, 95% CI 2.8-115.5, p < 0.003) and thrice weekly (odds ratio 10, 95% CI 1.6-64.8, p < 0.02) groups. CONCLUSION Prophylactic oral iron supplements when given intermittently were not effective in preventing iron deficiency anaemia in pregnancy.