Iron supplementation in pregnancy

Provision of routine iron supplementation to pregnant women who do not have iron deficiency anaemia (haemoglobin > 10 g/dL) results in a positive effect on women's iron status indicators, but there is little or no information about its impact on functional outcomes in either women or infants. The impact of routine iron supplementation on iron status indicators includes reduced prevalence of low pre-delivery haemoglobin (Hgb), low serum iron and ferritin, low Hgb at 6 weeks after delivery and more stainable iron in the bone marrow. Routine iron supplementation during pregnancy has no effect on the incidence of urinary tract infection, malaria (only one study), or hypertension in pregnancy, though there may be a small protective effect in terms of reduction in the rate of caesarean section. The impact of routine iron supplementation during pregnancy on birth weight (either incidence of low-birth-weight or of intrauterine growth retardation) or on incidence of congenital malformations has not been studied. In fact, infant outcomes in general have not been studied adequately.

There has been one randomized trial conducted in a well-nourished population that compared routine versus selective iron supplementation during pregnancy (supplementation only if Hgb (less than < 10 g/dL). This trial suggests a negative impact of routine iron supplementation on perinatal mortality when compared to selective supplementation (1).

In view of the fact that the biological effects of routine iron supplementation during pregnancy (such as caesarean section, birth weight, malaria, preterm delivery, Apgar scores, short-term memory, evaluated mostly in single studies), have not been sufficiently studied in non-anaemic pregnant women, the reviewer suggests that there is no evidence to recommend routine iron supplementation during pregnancy in well-nourished women despite the improvement in haematological indicators. Likewise, there is no evidence against the provision of routine iron supplementation in populations with high incidence of iron deficiency anaemia.

Randomized trials with iron supplementation for approximately 16 weeks to all pregnant women (anaemic and non-anaemic) women have been included in this review. The search strategy developed by the Pregnancy and Childbirth Group (accessible through the link in the review) has been used. The review does not include the randomized controlled trial by Preziosi et al. conducted in Nigeria (2).

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