Study: Intermittent iron supplementation is adequate for anemia prevention

Iron supplementation 2 to 3 times a week may prevent anemia in pregnant women as well as daily supplementation, according to a recent Cochrane systematic review published online July 11. In addition, the women may experience fewer side effects with intermittent supplementation, the authors found.

Daily iron supplementation has been the traditional recommendation in prenatal management for preventing iron-deficiency anemia during pregnancy, which can result in complications such as an increased risk of low birth weight or mortality, according to Juan Pablo Peña-Rosas of the World Health Organization, Evidence and Programme Guidance, Department of Nutrition for Health and Development in Geneva, Switzerland, and colleagues. However, daily supplementation also carries side effects such as nausea, constipation, and the risk of too much iron, which the authors say can also result in complications, including low birth weight and premature birth.

The researchers examined 18 trials involving 4,072 pregnant women to assess the benefits and harms of intermittent supplementation with iron alone or in combination with folic acid or with multi-vitamin and mineral supplements. They found no clear differences between daily supplementation and intermittent supplementation for low birth weight (average risk ratio [RR] 0.96; 95% CI, 0.61–1.52, 7 studies), infant birth weight (mean difference -8.62 g; 95% CI, -52.76 g–35.52 g, 8 studies), or premature birth (average RR 1.82; 95% CI, 0.75–4.40, 4 studies).

In addition, women who took iron supplements up to 3 times a week on non-consecutive days were no more likely to suffer from anemia by the end of their pregnancies than those who took them daily, and they were less likely to report side effects (average RR 0.56; 95% CI, 0.37–0.84, intermittent 25.2%, daily 35.9% reported side effects).

Although the authors admit that the overall quality of the evidence for their review was low or very low, they concluded that intermittent supplementation may be a feasible alternative to daily iron supplementation among those pregnant women who are not anemic and have adequate antenatal care; however, they suggest future studies focus on establishing safe and effective intermittent doses and health implications.

“The present systematic review is the most comprehensive summary of the evidence assessing the benefits and harms of intermittent regimens on haematological and pregnancy outcomes. The findings suggest that intermittent iron plus folic acid regimens produce similar maternal and infant outcomes at birth as daily supplementation but are associated with fewer side effects,” they wrote.