Maternal vitamin B12 deficiency · pregnant women
It is very uncertain whether summary of findings table ‐ Vitamin B12 supplementation changes maternal vitamin B12 deficiency compared with placebo/no vitamin B12 supplementation (very low certainty).
1 finding from 1 review
Vitamin A deficiency · children aged between 6 months and 5 years
Vitamin A supplementation probably leads to lower vitamin A deficiency compared with placebo or usual care (moderate certainty).
1 finding from 1 review
Vitamin A deficiency · mortality and morbidity in term neonates
Neonatal vitamin A supplementation showed no clear difference in vitamin A deficiency (serum retinol < 0.70 micromol/L) at 6 weeks of… compared with control (high certainty).
2 findings from 1 review
Stillbirth · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation showed no clear difference in stillbirth compared with placebo, no placebo or other supplements (moderate certainty).
1 finding from 1 review
Preterm birth · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation showed no clear difference in preterm birth (less than 37 weeks' gestation) compared with placebo, no placebo or other supplements (high certainty).
1 finding from 1 review
Pre‐eclampsia · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation showed no clear difference in clinical pre‐eclampsia (random‐effects model) compared with placebo, no placebo or other supplements (moderate certainty).
1 finding from 1 review
Intrauterine growth restriction · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation showed no clear difference in intrauterine growth restriction (various definitions) compared with placebo, no placebo or other supplements (high certainty).
1 finding from 1 review
Preterm prelabour rupture of membranes · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation showed no clear difference in prelabour rupture of fetal membranes ‐ preterm compared with placebo, no placebo or other supplements (low certainty).
1 finding from 1 review
Bleeding episodes (placental abruption) · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate dietary intake of vitamin…
Any vitamin E supplementation leads to lower bleeding episodes (placental abruption) compared with placebo, no placebo or other supplements (high certainty).
1 finding from 1 review
Maternal anaemia · pregnant women
It is very uncertain whether summary of findings table ‐ Vitamin B12 supplementation changes maternal anaemia compared with placebo/no vitamin B12 supplementation (very low certainty).
1 finding from 1 review
Miscarriage and spontaneous abortion · pregnant women
1 finding from 1 review
Low birthweight · pregnant women
Summary of findings table ‐ Vitamin B12 supplementation showed no clear difference in low birthweight (< 2500 g) compared with placebo/no vitamin B12 supplementation (low certainty).
1 finding from 1 review
Preterm birth · pregnant women
Summary of findings table ‐ Vitamin B12 supplementation showed no clear difference in preterm birth (< 37 weeks) compared with placebo/no vitamin B12 supplementation (low certainty).
1 finding from 1 review
Child cognitive outcomes · pregnant women
1 finding from 1 review
Neural tube defects ‐ not reported · pregnant women
The review found no eligible studies for this question.
1 finding from 1 review
no estimate extracted
Studies not reported
No studies found
All‐cause mortality · children aged between 6 months and 5 years
Vitamin A supplementation leads to lower all‐cause mortality compared with placebo or usual care (high certainty).
1 finding from 1 review
Vomiting · children aged between 6 months and 5 years
Vitamin A supplementation probably leads to higher vomiting compared with placebo or usual care (moderate certainty).
1 finding from 1 review
Mortality due to diarrhoea · children aged between 6 months and 5 years
Vitamin A supplementation leads to lower mortality due to diarrhoea compared with placebo or usual care (high certainty).
1 finding from 1 review
Mortality due to measles · children aged between 6 months and 5 years
Vitamin A supplementation showed no clear difference in mortality due to measles compared with placebo or usual care (low certainty).
1 finding from 1 review
Mortality due to LRTI · children aged between 6 months and 5 years
Vitamin A supplementation showed no clear difference in mortality due to LRTI compared with placebo or usual care (low certainty).
1 finding from 1 review