Low birthweight · Women receiving supplements in pregnancy
Any intermittent iron regimen (with or without other vitamins and… showed no clear difference in low birthweight (less than 2500 g) compared with daily regimen (with same vitamins and minerals)‐infant outcomes (low certainty).
1 finding from 1 review
Participants with at least some Side Effects · Women receiving supplements in pregnancy
It is very uncertain whether any intermittent iron regimen (with or without other vitamins and… changes side effects (any reported throughout intervention period) compared with daily regimen (with same vitamins and minerals)‐maternal outcomes (very low certainty).
1 finding from 1 review
Severe anaemia at any time during second and third trimester (Hb less than 70 g/L) · Women receiving supplements in pregnancy
1 finding from 1 review
Maternal clinical malaria or other infection in pregnancy · Women receiving supplements in pregnancy
Any intermittent iron regimen (with or without other vitamins and… led to lower maternal clinical malaria or other infection in pregnancy compared with daily regimen (with same vitamins and minerals)‐maternal outcomes; GRADE not reported.
1 finding from 1 review
Birthweight (g) · Women receiving supplements in pregnancy
Any intermittent iron regimen (with or without other vitamins and… showed no clear difference in birthweight (g) compared with daily regimen (with same vitamins and minerals)‐infant outcomes (low certainty).
1 finding from 1 review
Gestational age (preterm birth < 37 weeks) · Women receiving supplements in pregnancy
Any intermittent iron regimen (with or without other vitamins and… showed no clear difference in premature birth (less than 37 weeks of gestation) compared with daily regimen (with same vitamins and minerals)‐infant outcomes (low certainty).
1 finding from 1 review
Neonatal mortality · Women receiving supplements in pregnancy
It is very uncertain whether any intermittent iron regimen (with or without other vitamins and… changes neonatal death (within 28 days after delivery) compared with daily regimen (with same vitamins and minerals)‐infant outcomes (very low certainty).
1 finding from 1 review
Congenital anomalies (including neural tube defects) · Women receiving supplements in pregnancy
1 finding from 1 review
Maternal anaemia at term (Hb less than 110 g/L at 37 weeks' gestation or more) (ALL) · Women receiving supplements in pregnancy
It is very uncertain whether any intermittent iron regimen (with or without other vitamins and… changes maternal anaemia at term (Hb less than 110 g/L at 37 weeks'… compared with daily regimen (with same vitamins and minerals)‐maternal outcomes (very low certainty).
1 finding from 1 review
Iron deficiency at term (as defined by trialists, based on any indicator of iron status at 37 wk gestation or more) · Women receiving supplements in pregnancy
1 finding from 1 review
Maternal iron‐deficiency anaemia at term (Hb less than 110 g/L and at least 1 additional laboratory indicators at 37 weeks' gestation or more) · Women receiving supplements in pregnancy
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).
1 finding from 1 review
Maternal death · Women receiving supplements in pregnancy
Any intermittent iron regimen (with or without other vitamins and… led to lower maternal death (death while pregnant or within 42 days of… compared with daily regimen (with same vitamins and minerals)‐maternal outcomes; GRADE not reported.
1 finding from 1 review
Any adverse effects · 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
Maternal adverse events · pregnant women and their infants..
The review found no eligible studies for this question.
1 finding from 1 review
no estimate extracted
Studies not reported
No studies found
Preterm birth · pregnant women and their infants..
Vitamin D + calcium supplementation may leads to higher preterm birth (less than 37 weeks' gestation) compared with placebo or no intervention (low certainty).
1 finding from 1 review
Low birthweight · pregnant women and their infants..
It is very uncertain whether vitamin D + calcium supplementation changes low birthweight (less than 2500 g) compared with placebo or no intervention (very low certainty).
1 finding from 1 review
Pre‐eclampsia · pregnant women and their infants..
Vitamin D + calcium supplementation probably leads to lower pre‐eclampsia compared with placebo or no intervention (moderate certainty).
1 finding from 1 review
Gestational diabetes · pregnant women and their infants..
It is very uncertain whether vitamin D + calcium supplementation changes gestational diabetes compared with placebo or no intervention (very low certainty).
1 finding from 1 review
Spina bifida · health: non‐randomised studies
It is very uncertain whether wheat flour or wheat flour products fortified with folic acid plus… changes spina bifida compared with unfortified wheat flours or wheat flour products (not containing… (very low certainty).
1 finding from 1 review
RR 0.29 [0.16, 0.56]
8037 participants
Very low
Encephalocoele · health: non‐randomised studies
It is very uncertain whether wheat flour or wheat flour products fortified with folic acid plus… changes encephalocoele compared with unfortified wheat flours or wheat flour products (not containing… (very low certainty).
1 finding from 1 review
RR 0.26 [0.13, 0.56]
8037 participants
Very low