Many pregnant women are urged to take a daily iron supplement to prevent anemia. But a new analysis of studies has found taking iron supplements one to three times a week is just as effective at preventing the blood disease.
The review, which examined 18 studies involving 4,072 women by the nonprofit Cochrane Collaborative research group, also found women experienced fewer side effects when taking iron supplements intermittently rather than daily.
"Intermittent iron supplementation could be considered as a feasible alternative to daily supplementation for preventing anemia during pregnancy, particularly in developed countries where anemia in pregnancy is not a public health problem and there is good antenatal care for monitoring anemia status," said lead researcher Juan Pablo Peña-Rosas, a health specialist with the Department of Nutrition for Health and Development at the World Health Organization in Switzerland. "At the moment evidence is limited and the quality of the trials included in our review was generally low."
Iron deficiency can cause anemia in pregnant women, increasing the risk of complications. It also raises the odds of a baby being born with low birth weight and having delayed growth and development later in life.
Typically, doctors recommend daily supplements containing iron and folic acid, started as early in the pregnancy as possible.
For the new analysis, researchers reviewed 18 trials involving pregnant women who took iron supplements alone, with folic acid or with multi-vitamin and mineral supplements. They found women who took iron supplements once, twice or three times a week were no more likely to suffer from anemia than those who took them daily, and their babies were no more likely to be born early or have a low birth weight. Furthermore, those taking the supplements intermittently were less likely to experience nausea, constipation and high hemoglobin levels during pregnancy.
The review authors said more research is needed to clarify safe maternal iron doses and their effects on infants.