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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 |
|---|---|---|---|
Fetal growth (biometry) + umbilical artery Doppler vs fetal growth Gestational age at birth (weeks) · women with twin pregnancies were randomised from 25 weeks Regimens of ultrasound surveillance for twin pregnancies for improving outcomes (2017) · Cochrane | MD 0.1 | 1 study · 526 participants | Moderate |
Fetal growth (biometry) + umbilical artery Doppler vs fetal growth Caesarean section (any) · women with twin pregnancies were randomised from 25 weeks Regimens of ultrasound surveillance for twin pregnancies for improving outcomes (2017) · Cochrane | RR 1 [0.81, 1.23] | 1 study · 526 participants | High |
Fetal growth (biometry) + umbilical artery Doppler vs fetal growth Induction of labour · women with twin pregnancies were randomised from 25 weeks Regimens of ultrasound surveillance for twin pregnancies for improving outcomes (2017) · Cochrane | RR 1.1 [0.8, 1.5] | 1 study · 526 participants | Moderate |
Fetal growth (biometry) + umbilical artery Doppler vs fetal growth Antenatal admission to hospital · women with twin pregnancies were randomised from 25 weeks Regimens of ultrasound surveillance for twin pregnancies for improving outcomes (2017) · Cochrane | RR 0.96 [0.8, 1.15] | 1 study · 526 participants | High |
Assessment vs direct admission Length of labour (hours) · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | no estimate extracted | 1 study · 209 participants | Low |
Home support vs telephone triage Rate of instrumental vaginal birth · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.95 [0.79, 1.15] | 2 studies · 4933 participants | Low |
Home support vs telephone triage Serious maternal morbidity · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.93 [0.61, 1.42] | 1 study · 3474 participants | Low |
Home support vs telephone triage Use of epidural or any regional anaesthesia · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.95 [0.87, 1.05] | 3 studies · 5168 participants | Low |
Home support vs telephone triage Neonatal admission to special care · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.84 [0.5, 1.42] | 3 studies · 5170 participants | Very low |
Home support vs telephone triage Apgar score < 7 at 5 minutes · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 1.19 [0.71, 1.99] | 3 studies · 5170 participants | Low |
One‐to‐one structured care vs usual care Length of labour (hours) · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
One‐to‐one structured care vs usual care Rate of caesarean section · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.93 [0.84, 1.02] | 1 study · 4996 participants | High |
One‐to‐one structured care vs usual care Rate of instrumental vaginal birth · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.94 [0.82, 1.08] | 1 study · 4996 participants | High |
One‐to‐one structured care vs usual care Serious maternal morbidity · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 1.13 [0.84, 1.52] | 1 study · 4996 participants | Moderate |
One‐to‐one structured care vs usual care Use of epidural or any regional anaesthesia · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 1 [0.99, 1.01] | 1 study · 4996 participants | High |
Assessment vs direct admission Rate of caesarean section · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.72 [0.3, 1.72] | 1 study · 209 participants | Very low |
One‐to‐one structured care vs usual care Neonatal admission to special care · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.98 [0.8, 1.21] | 1 study · 4989 participants | High |
One‐to‐one structured care vs usual care Apgar score < 7 at 5 minutes · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 1.07 [0.64, 1.79] | 1 study · 4989 participants | Moderate |
Assessment vs direct admission Rate of instrumental vaginal birth · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.86 [0.58, 1.26] | 1 study · 209 participants | Very low |
Assessment vs direct admission Serious maternal morbidity · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Assessment vs direct admission Use of epidural or any regional anaesthesia · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 0.87 [0.78, 0.98] | 1 study · 209 participants | Low |
Assessment vs direct admission Neonatal admission to special care · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | no estimate extracted | NR | No studies |
Assessment vs direct admission Apgar score < 7 at 5 minutes · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 2.97 [0.12, 72.12] | 1 study · 209 participants | Very low |
Home support vs telephone triage Length of labour (hours) · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | no estimate extracted | 1 study · 3474 participants | Low |
Home support vs telephone triage Rate of caesarean section · healthy pregnant women Assessment and support during early labour for improving birth outcomes (2017) · Cochrane | RR 1.05 [0.95, 1.17] | 3 studies · 5170 participants | Moderate |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal hypothyroidism ‐ pregnancy · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 1.9 [0.57, 6.38] | 1 study · 365 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (child outcomes) Low birthweight · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.56 [0.26, 1.23] | 2 studies · 377 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (child outcomes) Neonatal hypothyroidism or elevated TSH · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.58 [0.11, 3.12] | 1 study · 219 participants | Very low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (child outcomes) Neonatal adverse effect: elevated TPO‐ab · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.61 [0.07, 5.7] | 1 study · 108 participants | Very low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (child outcomes) Child adverse effect: hyperthyroidism · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | no estimate extracted | NR | No studies |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal hypothyroidism ‐ postpartum · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.44 [0.06, 3.42] | 3 studies · 540 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Preterm birth · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.71 [0.3, 1.66] | 2 studies · 376 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal adverse effect: elevated thyroid peroxidase antibodies ‐ pregnancy · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.95 [0.44, 2.07] | 1 study · 359 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal adverse effect: elevated TPO‐ab ‐ postpartum · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 1.01 [0.78, 1.3] | 3 studies · 397 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal adverse effect: hyperthyroidism ‐ pregnancy · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 1.9 [0.57, 6.38] | 1 study · 365 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal adverse effect: hyperthyroidism ‐ postpartum · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.32 [0.11, 1.91] | 3 studies · 543 participants | Low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (maternal outcomes) Maternal adverse effect: digestive intolerance ‐ pregnancy · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 15.33 [2.07, 113.7] | 1 study · 76 participants | Very low |
Any supplement containing iodine vs same supplement without iodine or no treatment/placebo (child outcomes) Perinatal mortality · women during the preconception, pregnancy and postpartum period Iodine supplementation for women during the preconception, pregnancy and postpartum period (2017) · Cochrane | RR 0.66 [0.42, 1.03] | 1 study · 399 participants | Low |
Lispro vs regular insulin (Different insulin types within similar insulin regimens) Macrosomia · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Human insulin vs animal insulin (Different insulin types within similar insulin regimens) Pre‐eclampsia · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Human insulin vs animal insulin (Different insulin types within similar insulin regimens) Caesarean section · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Human insulin vs animal insulin (Different insulin types within similar insulin regimens) Fetal anomaly · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Human insulin vs animal insulin (Different insulin types within similar insulin regimens) Birth trauma including shoulder dystocia, nerve palsy, and fracture · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Human insulin vs animal insulin (Different insulin types within similar insulin regimens) Composite outcome measure of neonatal morbidity · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Pre‐mixed insulin (70 NPH/30 REG) vs self‐mixed split dose insulin (Different insulin regimens with similar insulin types used within the regimen) Macrosomia · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | RR 0.49 [0.09, 2.54] | 1 study · 93 participants | Very low |
Pre‐mixed insulin (70 NPH/30 REG) vs self‐mixed split dose insulin (Different insulin regimens with similar insulin types used within the regimen) Perinatal death · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Pre‐mixed insulin (70 NPH/30 REG) vs self‐mixed split dose insulin (Different insulin regimens with similar insulin types used within the regimen) Pre‐eclampsia · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Pre‐mixed insulin (70 NPH/30 REG) vs self‐mixed split dose insulin (Different insulin regimens with similar insulin types used within the regimen) Caesarean section 4 · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | RR 0.57 [0.25, 1.32] | 1 study · 93 participants | Very low |
Pre‐mixed insulin (70 NPH/30 REG) vs self‐mixed split dose insulin (Different insulin regimens with similar insulin types used within the regimen) Fetal anomaly · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Lispro vs regular insulin (Different insulin types within similar insulin regimens) Perinatal death · pregnant women with pre‐existing diabetes Different insulin types and regimens for pregnant women with pre‐existing diabetes (2017) · Cochrane | no estimate extracted | 1 study · 33 participants | Very low |