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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.

Limit to evidence status or GRADE (optional)

3,601 questions in 252 reviews · Pregnancy and Childbirth

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
Setting of BP measurement: self‐measurement vs conventional clinic measurement
Number of antenatal hospital admissions · pregnant women with chronic or gestational hypertension
Setting and techniques for monitoring blood pressure during pregnancy (2020) · Cochrane
no estimate extractedNRNo studies
Setting of BP measurement: self‐measurement vs conventional clinic measurement
Maternal admission to intensive care · pregnant women with chronic or gestational hypertension
Setting and techniques for monitoring blood pressure during pregnancy (2020) · Cochrane
RR 1.54 [0.06, 37.25]1 study · 154 participantsLow
Setting of BP measurement: self‐measurement vs conventional clinic measurement
Induction of labour · pregnant women with chronic or gestational hypertension
Setting and techniques for monitoring blood pressure during pregnancy (2020) · Cochrane
RR 1.09 [0.82, 1.45]1 study · 154 participantsLow
Setting of BP measurement: self‐measurement vs conventional clinic measurement
Neonatal outcomes · pregnant women with chronic or gestational hypertension
Setting and techniques for monitoring blood pressure during pregnancy (2020) · Cochrane
no estimate extractedNRNo studies
Setting of BP measurement: self‐measurement vs conventional clinic measurement
Stillbirth (death after 24 weeks inutero) · pregnant women with chronic or gestational hypertension
Setting and techniques for monitoring blood pressure during pregnancy (2020) · Cochrane
RR 2.57 [0.13, 52.63]1 study · 154 participantsLow
Aspirin vs placebo
Live birth · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.94 [0.71, 1.25]1 study · 40 participantsVery low
Heparin plus aspirin vs aspirin
Live birth · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.27 [1.09, 1.49]5 studies · 1295 participantsLow
Heparin plus aspirin vs aspirin
Pre‐eclampsia · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.57 [0.1, 3.14]2 studies · 82 participantsLow
Heparin plus aspirin vs aspirin
Adverse events in the mother ‐ Bleeding · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.65 [0.19, 14.03]1 study · 31 participantsLow
Heparin plus aspirin vs aspirin
Adverse events in the mother ‐ Heparin‐induced thrombocytopenia · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extracted2 studies · 140 participantsUngraded
Heparin plus aspirin vs aspirin
Adverse events in the mother ‐ Allergic reactions · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extracted1 study · 90 participantsUngraded
Heparin plus aspirin vs aspirin
Venous thromboembolism · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extracted3 studies · 182 participantsUngraded
Heparin plus aspirin vs aspirin
Arterial thromboembolism · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extracted3 studies · 182 participantsUngraded
Heparin plus aspirin vs aspirin
Pregnancy loss · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.48 [0.32, 0.71]5 studies · 1295 participantsLow
Heparin plus aspirin vs aspirin
Preterm delivery of a live infant · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.933 studies · 156 participantsVery low
Heparin plus aspirin vs aspirin
Intrauterine growth restriction · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.85 [0.33, 2.19]3 studies · 151 participantsVery low
Aspirin vs placebo
Pre‐eclampsia · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.06 [0.25, 4.52]1 study · 33 participantsVery low
Heparin plus aspirin vs aspirin
Adverse events in the child ‐ Congenital malformations · women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extracted1 study · 51 participantsUngraded
Aspirin vs placebo
Adverse events in the mother ‐ Bleeding · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.29 [0.6, 2.77]1 study · 40 participantsVery low
Aspirin vs placebo
Venous thromboembolism · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extractedNRNo studies
Aspirin vs placebo
Arterial thromboembolism · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
no estimate extractedNRNo studies
Aspirin vs placebo
Pregnancy loss · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.33 [0.34, 5.21]1 study · 40 participantsVery low
Aspirin vs placebo
Preterm delivery of a live infant · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 5.29 [0.27, 102.49]1 study · 33 participantsVery low
Aspirin vs placebo
Intrauterine growth restriction · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 0.27 [0.03, 2.13]1 study · 33 participantsVery low
Aspirin vs placebo
Adverse events in the child ‐ Congenital malformations · improving pregnancy outcomes in women with persistent antiphospholipid antibodies and recurrent pregnancy loss
Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid… (2020) · Cochrane
RR 1.06 [0.07, 15.6]1 study · 33 participantsVery low
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Serious neonatal morbidity (Reported in Miller 2014 as 'composite adverse outcome', which included the following neonatal morbidities: respiratory distress syndrome, necrotising enterocolitis, intraventricular haemorrhage, retinopathy of prematuri...
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
RR 0.62 [0.31, 1.24]1 study · 50 participantsVery low
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Perinatal loss: all ‐ including miscarriages and stillbirth (Note: data not available for neonatal death)
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
RR 0.46 [0.13, 1.64]1 study · 50 participantsVery low
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Baby discharged home healthy
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
no estimate extractedNRNo studies
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Neonatal death before discharge
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
no estimate extractedNRNo studies
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Stillbirth: intrauterine death at 24 or more weeks
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
no estimate extracted1 study · 50 participantsVery low
Cervical cerclage in combination with antibiotics and tocolytics vs cervical cerclage alone
Preterm birth < 34 completed weeks of pregnancy
Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in… (2020) · Cochrane
RR 0.78 [0.44, 1.4]1 study · 50 participantsVery low
Probiotic vs placebo
Hypertensive disorders (including pre‐eclampsia, pregnancy‐induced hypertension, eclampsia) · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
RR 1.5 [0.64, 3.53]3 studies · 256 participantsLow
Probiotic vs placebo
Composite serious neonatal outcomes (variously defined by trials, e.g. infant death, shoulder dystocia, bone fracture, or nerve palsy · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Neurosensory disability · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Neonatal hypoglycaemia requiring treatment (variously defined) · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
RR 0.85 [0.39, 1.84]3 studies · 177 participantsLow
Probiotic vs placebo
Adiposity (neonatal/child/child as an adult) · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Diabetes(type1 or type2) or impaired glucose tolerance (child/adult) · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Subsequent development of type 2 diabetes · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Mode of birth (caesarean) · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
RR 0.64 [0.3, 1.35]3 studies · 267 participantsLow
Probiotic vs placebo
Induction of labour · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
RR 1.33 [0.74, 2.37]1 study · 127 participantsVery low
Probiotic vs placebo
Perineal trauma · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Postnatal weight retention or return to pre‐pregnancy weight · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Postnatal depression · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Perinatal (fetal and neonatal) mortality · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Probiotic vs placebo
Large‐for‐gestational age > 90 centile · pregnant women diagnosed with gestational diabetes
Probiotic treatment for women with gestational diabetes to improve maternal and infant health and well‐being (2020) · Cochrane
RR 0.73 [0.35, 1.52]2 studies · 174 participantsLow
Paracervical block vs intravenous diazepam/pethidine analgesia
Pain intensity · women with persistent or prolonged retention of placenta
Anaesthesia/analgesia for manual removal of retained placenta (2020) · Cochrane
no estimate extractedNRNo studies
Paracervical block vs intravenous diazepam/pethidine analgesia
Adverse events · women with persistent or prolonged retention of placenta
Anaesthesia/analgesia for manual removal of retained placenta (2020) · Cochrane
no estimate extractedNRNo studies
Paracervical block vs intravenous diazepam/pethidine analgesia
Postpartum haemorrhage (blood loss ≥ 500 mL) · women with persistent or prolonged retention of placenta
Anaesthesia/analgesia for manual removal of retained placenta (2020) · Cochrane
no estimate extracted1 study · 30 participantsVery low
Paracervical block vs intravenous diazepam/pethidine analgesia
Requirement of additional analgesia or general anaesthesia · women with persistent or prolonged retention of placenta
Anaesthesia/analgesia for manual removal of retained placenta (2020) · Cochrane
no estimate extractedNRNo studies
Paracervical block vs intravenous diazepam/pethidine analgesia
Serious maternal morbidity · women with persistent or prolonged retention of placenta
Anaesthesia/analgesia for manual removal of retained placenta (2020) · Cochrane
no estimate extractedNRNo studies