Cochrane · systematic review · CD004073
Vitamin supplementation for preventing miscarriage
Balogun, OO, da Silva Lopes, K, Ota, E, et al. · Cochrane Database of Systematic Reviews · 2016 · Cochrane Library
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
12
current version
GRADE rated
10
No studies
2
Included studies
NR
No studies 2 · 16.7%Ungraded 0 · 0%Very low 0 · 0%Low 3 · 25%Moderate 4 · 33.3%High 3 · 25%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Questions and results
Current version onlyVitamin C and vitamin E versus placebo for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss Vitamin C and vitamin E vs placebo | RR 1.14 [0.92, 1.4] | 7 studies · 18949 participants | High |
Early or late miscarriage Vitamin C and vitamin E vs placebo | RR 0.9 [0.65, 1.26] | 4 studies · 13346 participants | Moderate Downgraded: imprecision |
Stillbirth Vitamin C and vitamin E vs placebo | RR 1.31 [0.97, 1.76] | 7 studies · 21442 participants | Moderate Downgraded: imprecision |
Any adverse effects of vitamin supplementation sufficient to stop supplementation Vitamin C and vitamin E vs placebo | RR 1.16 [0.39, 3.41] | 1 study · 739 participants | Moderate Downgraded: imprecision |
Vitamin A plus iron plus folate versus iron plus folate for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) ‐ Vitamin A + iron + folate versus iron + folate Vitamin A plus iron plus folate vs iron plus folate | RR 1.01 [0.61, 1.66] | 3 studies · 1640 participants | Low Downgraded: risk of bias |
Early or late miscarriage ‐ Vitamin A + iron + folate versus iron + folate Vitamin A plus iron plus folate vs iron plus folate | RR 0.86 [0.46, 1.62] | 2 studies · 1397 participants | Low Downgraded: risk of bias |
Stillbirth ‐ Vitamin A + iron + folate versus iron + folate Vitamin A plus iron plus folate vs iron plus folate | RR 1.29 [0.57, 2.91] | 3 studies · 1640 participants | Low Downgraded: risk of bias |
Any adverse effects Vitamin A plus iron plus folate vs iron plus folate | no estimate extracted | NR | No studies |
Multivitamin plus iron plus folate versus iron plus folate for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) ‐ Multivitamins + iron + folic acid versus iron + folic acid Multivitamin plus iron plus folate vs iron plus folate | RR 0.96 [0.93, 1] | 10 studies · 94948 participants | High |
Early or late miscarriage ‐ Multivitamin + iron + folic acid versus iron + folic acid Multivitamin plus iron plus folate vs iron plus folate | RR 0.98 [0.94, 1.03] | 10 studies · 94948 participants | Moderate Downgraded: publication bias |
Stillbirth ‐ Multivitamin + iron + folic acid versus iron + folic acid Multivitamin plus iron plus folate vs iron plus folate | RR 0.92 [0.85, 0.99] | 10 studies · 79851 participants | High |
Any adverse effects Multivitamin plus iron plus folate vs iron plus folate | no estimate extracted | NR | No studies |
Vitamin A versus placebo for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) Vitamin A vs placebo | RR 1.04 [0.92, 1.17] | 1 study · 11723 participants | High |
Neonatal death Vitamin A vs placebo | RR 1.09 [0.92, 1.3] | 1 study · 10214 participants | High |
Preterm birth Vitamin A vs placebo | RR 1.04 [0.89, 1.21] | 1 study · 11723 participants | Moderate Downgraded: imprecision, inconsistency |
Vitamin A versus B‐Carotene for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) Vitamin A vs B‐Carotene | RR 1.01 [0.9, 1.14] | 1 study · 11720 participants | High |
Neonatal death Vitamin A vs B‐Carotene | RR 1 [0.85, 1.18] | 1 study · 10228 participants | High |
Preterm birth Vitamin A vs B‐Carotene | RR 1.03 [0.88, 1.2] | 1 study · 11720 participants | Moderate Downgraded: imprecision, inconsistency |
Vitamin A plus iron plus folate versus iron plus folate for preventing miscarriage
Population: pregnant women
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Total fetal loss (including miscarriages or combined miscarriages and stillbirths) Vitamin A plus iron plus folate vs iron plus folate | RR 1.01 [0.61, 1.66] | 3 studies · 1640 participants | Very low Downgraded: imprecision |
Stillbirth Vitamin A plus iron plus folate vs iron plus folate | RR 1.29 [0.57, 2.91] | 3 studies · 1640 participants | Very low Downgraded: imprecision |
Preterm birth Vitamin A plus iron plus folate vs iron plus folate | RR 1.11 [0.59, 2.09] | 1 study · 700 participants | Low Downgraded: imprecision, inconsistency |
Birthweight (grams) Vitamin A plus iron plus folate vs iron plus folate | no estimate extracted | 1 study · 594 participants | Low Downgraded: imprecision, inconsistency |
Maternal anaemia Vitamin A plus iron plus folate vs iron plus folate | RR 0.96 [0.82, 1.12] | 1 study · 700 participants | Moderate Downgraded: imprecision, inconsistency |