Intravenous iron showed no clear difference in maternal mortality Clinical assessment compared with oral iron (low certainty).
The review found no eligible studies for this question.
It is very uncertain whether intravenous iron changes infections Clinical assessment compared with oral iron (very low certainty).
It is very uncertain whether intravenous iron changes constipation Reported by the women compared with oral iron (very low certainty).
It is very uncertain whether intravenous iron changes all gastrointestinal symptoms Reported by the women compared with oral iron (very low certainty).
Intravenous iron showed no clear difference in anaphylaxis or evidence of hypersensitivity Clinical assessment compared with oral iron (low certainty).
It is very uncertain whether any intermittent iron regimen (with or without other vitamins and… changes maternal iron‐deficiency anaemia at term (Hb less than 110 g/L and… compared with daily regimen (with same vitamins and minerals)‐maternal outcomes (very low certainty).
(Infant outcomes) Any supplements containing iron showed no clear difference in low birthweight (less than 2500 g) (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (low certainty).
(Infant outcomes) Any supplements containing iron showed no clear difference in preterm birth (less than 37 weeks of gestation) (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (moderate certainty).
(Infant outcomes) Any supplements containing iron showed no clear difference in neonatal death (within 28 days after delivery) (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (low certainty).
(Infant outcomes) Any supplements containing iron showed no clear difference in congenital anomalies (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (low certainty).
It is very uncertain whether (Maternal outcomes) Any supplements containing iron changes maternal severe anaemia at any time during second and third… compared with same supplements without iron or no treatment/placebo (no iron or… (very low certainty).
(Maternal outcomes) Any supplements containing iron showed no clear difference in infection during pregnancy (including urinary tract infections) (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (low certainty).
(Maternal outcomes) Any supplements containing iron may leads to lower maternal anaemia at term (Hb less than 110 g/L at 37 weeks'… compared with same supplements without iron or no treatment/placebo (no iron or… (low certainty).
It is very uncertain whether (Maternal outcomes) Any supplements containing iron changes maternal death (death while pregnant or within 42 days of… compared with same supplements without iron or no treatment/placebo (no iron or… (very low certainty).
It is very uncertain whether (Maternal outcomes) Any supplements containing iron changes side effects (any reported throughout the intervention period) (ALL) compared with same supplements without iron or no treatment/placebo (no iron or… (very low certainty).
(Infant outcomes) Any supplements containing iron and folic acid showed no clear difference in low birthweight (less than 2500 g) (ALL) compared with same supplements without iron nor folic acid (no iron nor folic acid… (low certainty).