Comparison 6. Supplementation with iron+other vitamins and minerals supplementation versus same other vitamins and minerals (without iron) supplementation.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Low birthweight (less than 2500 g) (ALL)	1	334	Risk Ratio (M‐H, Random, 95% CI)	0.51 [0.22, 1.15]
2 Birthweight (g) (ALL)	2	1116	Mean Difference (IV, Random, 95% CI)	55.70 [3.42, 107.97]
3 Preterm birth (less than 37 weeks of gestation) (ALL)	2	1127	Risk Ratio (M‐H, Random, 95% CI)	0.66 [0.41, 1.04]
4 Neonatal death (within 28 days after delivery) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
5 Congenital anomalies (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
6 Maternal anaemia at term (Hb less than 110 g/L at 37 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
7 Maternal iron deficiency at term (as defined by trialists, based on any indicator of iron status at 37 weeks' gestation or more)(ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
8 Maternal iron‐deficiency anaemia at term (Hb less than 110 g/L and at least one additional laboratory indicators at 37 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
9 Maternal death (death while pregnant or within 42 days of termination of pregnancy) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
10 Side effects (any reported throughout the intervention period) (ALL)	1	188	Risk Ratio (M‐H, Random, 95% CI)	0.77 [0.55, 1.07]
11 Maternal severe anaemia at any time during second and third trimester (Hb less than 70 g/L) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
12 Maternal clinical malaria	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
13 Infection during pregnancy (including urinary tract infections) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
14 Very low birthweight (less than 1500 g) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
15 Very premature birth (less than 34 weeks' gestation) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
16 Infant Hb concentration in the first 6 months (in g/L, counting the last reported measure after birth within this period) (ALL)	0	0	Mean Difference (IV, Random, 95% CI)	0.0 [0.0, 0.0]
17 Infant serum ferritin concentration in the first 6 months (in μg/L, counting the last reported measure after birth within this period) (ALL)	0	0	Mean Difference (IV, Random, 95% CI)	0.0 [0.0, 0.0]
18 Admission to special care unit (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
19 Maternal anaemia at or near term (Hb less than 110 g/L at 34 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
20 Maternal iron deficiency at or near term (as defined by trialists, based on any indicator of iron status at 34 weeks' gestation or more)(ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
21 Maternal iron‐deficiency anaemia at or near term (Hb less than 110 g/L and at least one additional laboratory indicators at 34 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
22 Maternal Hb concentration at or near term (in g/L at 34 weeks' gestation or more) (ALL)	2	809	Mean Difference (IV, Random, 95% CI)	10.85 [7.29, 14.42]
23 Maternal Hb concentration within 6 wk postpartum (in g/L) (ALL)	1	27	Mean Difference (IV, Random, 95% CI)	14.0 [3.56, 24.44]
24 Maternal high haemoglobin concentrations during second or third trimester (Hb more than 130 g/L) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
25 Maternal high haemoglobin concentrations at or near term (Hb more than 130 g/L at 34 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
26 Moderate anaemia at postpartum (Hb more than 80 g/L and less than 110 g/L) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
27 Maternal severe anaemia at or near term (Hb less than 70 g/L at 34 weeks' gestation or more) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
28 Severe anaemia at postpartum (Hb less than 80 g/L) (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
29 Puerperal infection (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
30 Antepartum haemorrhage (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
31 Postpartum haemorrhage (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
32 Transfusion provided (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
33 Constipation (ALL)	1	188	Risk Ratio (M‐H, Random, 95% CI)	0.77 [0.55, 1.07]
34 Nausea (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
35 Heartburn (ALL)	1	188	Risk Ratio (M‐H, Random, 95% CI)	1.49 [0.95, 2.34]
36 Vomiting (ALL)	1	188	Risk Ratio (M‐H, Random, 95% CI)	1.13 [0.58, 2.20]
37 Diarrhoea (ALL)	1	188	Risk Ratio (M‐H, Random, 95% CI)	0.53 [0.29, 0.96]
38 Maternal wellbeing/satisfaction (ALL)	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
39 Placental abruption (ALL)	1	782	Risk Ratio (M‐H, Random, 95% CI)	1.81 [0.46, 7.20]
40 Premature rupture of membranes (ALL)	1	782	Risk Ratio (M‐H, Random, 95% CI)	0.79 [0.44, 1.41]
41 Pre‐eclampsia (ALL)	1	782	Risk Ratio (M‐H, Random, 95% CI)	1.45 [0.67, 3.16]