Oral iron-based interventions for prevention of critical outcomes in pregnancy and postnatal care: An overview and update of systematic reviews

ObjectiveThe aim of this work was to summarize and update the evidence concerning oral iron-based interventions compared to placebo or no iron-based interventions to prevent critical outcomes in pregnancy or treat critical outcomes in the postpartum phase. MethodPublished systematic reviews (Feb 2018) and primary studies (from 2015 to March 2018) retrieved from MEDLINE, EMBASE, and the Cochrane Library were examined. The AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool was used to assess the quality of reviews. GRADE was used to rate the quality of the evidence for critical outcomes. ResultsAntenatal care: Compared to placebo/no treatment, iron-based therapies reduced maternal anemia at term by 59% (seven trials at low risk of bias, RR 0.41, 95% CI 0.23-0.73; I-2 = 86%; moderate-quality evidence) and maternal iron deficiency anemia by 67% (RR 0.33, 95% CI 0.16-0.69; I-2 = 49%). There was no evidence of difference between iron-based therapies vs control in terms of side effects (RR 1.42, 95% CI 0.91-2.21), preterm delivery (13 studies: RR 0.93, 95% CI 0.84-1.03; low-quality evidence), low birthweight (RR 0.94, 95% CI 0.79-1.13; low-quality evidence) and infant mortality (RR 0.93, 0.72-1.20; low-quality evidence). Postnatal careThere was insufficient evidence to determine whether iron-based therapies can reduce postpartum anemia. ConclusionIron supplementation is effective in preventing maternal anemia at term but not low birthweight, preterm delivery or infant mortality.