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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.
3,601 questions in 252 reviews · Pregnancy and Childbirth
current versionsNo studies 726 · 20.2%Ungraded 421 · 11.7%Very low 828 · 23%Low 993 · 27.6%Moderate 486 · 13.5%High 147 · 4.1%
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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Tetanus toxoid vs influenza vaccine All causes of deaths ‐ 2 or 3 doses · women aged between 13 and 45 years. Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 0.31 [0.17, 0.55] | 1 study · 688 participants | Moderate |
Tetanus toxoid vs influenza vaccine Neonatal tetanus cases ‐ Any dose · women aged between 13 and 45 years. Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 0.2 [0.1, 0.4] | 1 study · 1182 participants | Moderate |
Tetanus diphtheria toxoid immunisation of women of reproductive age vs cholera toxoid Neonatal mortality in the first 28 days of life · women of reproductive age ≥ 15 years. Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 0.68 [0.56, 0.82] | 1 study · 8641 participants | Low |
Tetanus diphtheria toxoid immunisation of women of reproductive age vs cholera toxoid Neonatal mortality between day 4‐14 of life · women of reproductive age ≥ 15 years. Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 0.38 [0.27, 0.55] | 1 study · 8641 participants | Low |
Local and systemic reactions after administration of Tetanus Diphtheria acelluar Pertussis vaccine vs saline placebo Injection site reactions ‐ pain at injection site · patients with local and systemic reactions Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 5.68 [1.54, 20.94] | 1 study · 48 participants | Moderate |
Local and systemic reactions after administration of Tetanus Diphtheria acelluar Pertussis vaccine vs saline placebo Injection site reactions ‐ erythema ‐ redness · patients with local and systemic reactions Vaccines for women for preventing neonatal tetanus (2015) · Cochrane | RR 1.36 [0.15, 12.05] | 1 study · 48 participants | Moderate |
Any vitamin E supplementation vs placebo, no placebo or other supplements Stillbirth · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 1.17 [0.88, 1.56] | 9 studies · 19023 participants | Moderate |
Any vitamin E supplementation vs placebo, no placebo or other supplements Preterm birth (less than 37 weeks' gestation) · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 0.98 [0.88, 1.09] | 11 studies · 20565 participants | High |
Any vitamin E supplementation vs placebo, no placebo or other supplements Clinical pre‐eclampsia (random‐effects model) · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 0.91 [0.79, 1.06] | 14 studies · 20878 participants | Moderate |
Any vitamin E supplementation vs placebo, no placebo or other supplements Intrauterine growth restriction (various definitions) · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 0.98 [0.91, 1.06] | 11 studies · 20202 participants | High |
Any vitamin E supplementation vs placebo, no placebo or other supplements Prelabour rupture of fetal membranes ‐ preterm · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 1.27 [0.93, 1.75] | 5 studies · 1999 participants | Low |
Any vitamin E supplementation vs placebo, no placebo or other supplements Bleeding episodes (placental abruption) · pregnant women receiving vitamin E supplementation or control, living in areas where there is either inadequate… Vitamin E supplementation in pregnancy (2015) · Cochrane | RR 0.64 [0.44, 0.93] | 7 studies · 14922 participants | High |
Intervention NR Stillbirth · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 1.15 [0.89, 1.49] | 11 studies · 20038 participants | Moderate |
Intervention NR Intrauterine growth restriction · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 0.98 [0.91, 1.06] | 12 studies · 20361 participants | High |
Intervention NR Preterm birth (< 37 weeks' gestation) · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 0.99 [0.9, 1.1] | 16 studies · 22250 participants | High |
Intervention NR Preterm prelabour rupture of membranes · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 0.98 [0.7, 1.36] | 10 studies · 16825 participants | Low |
Intervention NR Clinical pre‐eclampsia · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 0.92 [0.8, 1.05] | 16 studies · 21956 participants | Moderate |
Intervention NR Placental abruption · All pregnant women receiving either vitamin C supplementation or control either in areas where there is inadequate… Vitamin C supplementation in pregnancy (2015) · Cochrane | RR 0.64 [0.44, 0.92] | 8 studies · 15755 participants | High |
Oral betamimetic vs placebo Preterm labour · pregnant women with a twin pregnancy Prophylactic oral betamimetics for reducing preterm birth in women with a twin pregnancy (2015) · Cochrane | RR 0.37 [0.17, 0.78] | 2 studies · 194 participants | Low |
Oral betamimetic vs placebo Prelabour rupture of membranes · pregnant women with a twin pregnancy Prophylactic oral betamimetics for reducing preterm birth in women with a twin pregnancy (2015) · Cochrane | RR 1.42 [0.42, 4.82] | 1 study · 144 participants | Low |
Oral betamimetic vs placebo Preterm birth (less than 37 weeks' gestation) · pregnant women with a twin pregnancy Prophylactic oral betamimetics for reducing preterm birth in women with a twin pregnancy (2015) · Cochrane | RR 0.85 [0.65, 1.1] | 4 studies · 276 participants | Low |
Oral betamimetic vs placebo Very preterm birth (less than 34 weeks' gestation) · pregnant women with a twin pregnancy Prophylactic oral betamimetics for reducing preterm birth in women with a twin pregnancy (2015) · Cochrane | RR 0.47 [0.15, 1.5] | 1 study · 144 participants | Low |
(Infant outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Low birthweight (less than 2500 g) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.84 [0.69, 1.03] | 11 studies · 17613 participants | Low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Maternal severe anaemia at any time during second and third trimester (Hb less than 70 g/L) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.22 [0.01, 3.2] | 9 studies · 2125 participants | Very low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Infection during pregnancy (including urinary tract infections) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 1.21 [0.33, 4.46] | 1 study · 727 participants | Low |
(Infant outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Low birthweight (less than 2500 g) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 1.07 [0.31, 3.74] | 2 studies · 1311 participants | Low |
(Infant outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Birthweight (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | no estimate extracted | 2 studies · 1365 participants | Moderate |
(Infant outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Preterm birth (less than 37 weeks of gestation) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 1.55 [0.4, 6] | 3 studies · 1497 participants | Low |
(Infant outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Neonatal death (within 28 days after delivery) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.81 [0.51, 1.3] | 3 studies · 1793 participants | Low |
(Infant outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Congenital anomalies (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.7 [0.35, 1.4] | 1 study · 1652 participants | Low |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Maternal anaemia at term (Hb less than 110 g/L at 37 weeks' gestation or more) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.34 [0.21, 0.54] | 3 studies · 346 participants | Moderate |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Maternal iron deficiency at term (as defined by trialists, based on any indicator of iron status at 37 weeks' gestation or more) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.24 [0.06, 0.99] | 1 study · 131 participants | Low |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Maternal death (death while pregnant or within 42 days of termination of pregnancy) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | no estimate extracted | 1 study · 131 participants | Low |
(Infant outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Birthweight (g) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | no estimate extracted | 15 studies · 18590 participants | Moderate |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Side effects (any reported throughout the intervention period) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 44.32 [2.77, 709.09] | 1 study · 456 participants | Moderate |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Maternal severe anaemia at any time during second and third trimester (Hb less than 70 g/L) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.12 [0.02, 0.63] | 4 studies · 506 participants | Very low |
(Maternal outcomes) Any supplements containing iron and folic acid vs same supplements without iron nor folic acid (no iron nor folic acid or placebo) Infection during pregnancy (including urinary tract infections) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 1 [0.15, 6.53] | 1 study · 48 participants | Very low |
(Infant outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Preterm birth (less than 37 weeks of gestation) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.93 [0.84, 1.03] | 13 studies · 19286 participants | Moderate |
(Infant outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Neonatal death (within 28 days after delivery) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.91 [0.71, 1.18] | 4 studies · 16603 participants | Low |
(Infant outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Congenital anomalies (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.88 [0.58, 1.33] | 4 studies · 14636 participants | Low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Maternal anaemia at term (Hb less than 110 g/L at 37 weeks' gestation or more) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.3 [0.19, 0.46] | 14 studies · 2199 participants | Low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Maternal iron deficiency at term (as defined by as defined by trialists, based on any indicator of iron status at 37 weeks's gestation or more) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.43 [0.27, 0.66] | 7 studies · 1256 participants | Low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Maternal death (death while pregnant or within 42 days of termination of pregnancy) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 0.33 [0.01, 8.19] | 2 studies · 12560 participants | Very low |
(Maternal outcomes) Any supplements containing iron vs same supplements without iron or no treatment/placebo (no iron or placebo) Side effects (any reported throughout the intervention period) (ALL) · Pregnant women of any gestational age and parity Daily oral iron supplementation during pregnancy (2015) · Cochrane | RR 1.29 [0.83, 2.02] | 11 studies · 2423 participants | Very low |
Pneumococcal vaccine vs control vaccine Neonatal death due to pneumococcal infection · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | no estimate extracted | 0 participants | Ungraded |
Pneumococcal vaccine vs control vaccine Neonatal infection ‐ Pneumonia · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | RR 0.58 [0.18, 1.9] | 1 study · 149 participants | Low |
Pneumococcal vaccine vs control vaccine Neonatal infection ‐ Meningitis · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | RR 3.04 [0.13, 73.44] | 1 study · 149 participants | Low |
Pneumococcal vaccine vs control vaccine Neonatal infection ‐ Otitis media · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | RR 0.14 [0.01, 2.75] | 1 study · 149 participants | Low |
Pneumococcal vaccine vs control vaccine Neonatal infection ‐ All infections · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | RR 0.66 [0.3, 1.46] | 2 studies · 241 participants | Low |
Pneumococcal vaccine vs control vaccine Pneumococcal colonization ‐ At 2‐3 months of age · Pregnant women undergoing vaccination to prevent infant infection Pneumococcal vaccination during pregnancy for preventing infant infection (2015) · Cochrane | RR 1.13 [0.46, 2.78] | 2 studies · 146 participants | Low |