What do systematic reviews say?

Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo)

(Maternal outcomes) Any supplements containing iron and folic acid probably leads to lower maternal anaemia at term (Hb less than 110 g/L at 37 weeks'… compared with same supplements without iron nor folic acid (no iron nor folic acid… (moderate certainty).

• Daily oral iron supplementation during pregnancy 2015 · Cochrane Headline outcomes only
  RR 0.34 [0.21, 0.54]
  3 studies · 346 participants
  Moderate