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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 |
|---|---|---|---|
Early vs second trimester amniocentesis Laboratory failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 9.76 [3.49, 27.26] | 1 study · 4368 participants | High |
Early vs second trimester amniocentesis Known false negative after birth · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 3 [0.12, 73.67] | 1 study · 4368 participants | Moderate |
Early vs second trimester amniocentesis Known false negative after birth ‐ Incorrect sex determination · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 5 [0.24, 104.18] | 1 study · 4368 participants | Moderate |
Early vs second trimester amniocentesis Delivery before 33 weeks · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Early vs second trimester amniocentesis Anomalies (all recorded) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.73 [1.26, 2.38] | 1 study · 4334 participants | High |
Transabdominal chorionic villus sampling vs second trimester amniocentesis All known pregnancy loss (including termination of pregnancy) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.9 [0.66, 1.23] | 1 study · 2234 participants | Low |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Spontaneous miscarriage · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.77 [0.49, 1.21] | 1 study · 2069 participants | Low |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Sampling failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Laboratory failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Second trimester amniocentesis vs control Spontaneous miscarriage · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.6 [1.02, 2.52] | 1 study · 4606 participants | High |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Known false negative after birth · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Delivery before 33 weeks · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Transabdominal chorionic villus sampling vs second trimester amniocentesis Perinatal deaths (stillbirths and neonatal deaths in the first week of life) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.18 [0.4, 3.51] | 1 study · 2069 participants | Low |
Transcervical vs transabdominal chorionic villus sampling All known pregnancy loss (including termination of pregnancy) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.16 [0.81, 1.65] | 5 studies · 7978 participants | Very low |
Transcervical vs transabdominal chorionic villus sampling Spontaneous miscarriage · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.68 [0.79, 3.58] | 4 studies · 3384 participants | Very low |
Transcervical vs transabdominal chorionic villus sampling Sampling failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.79 [1.13, 2.82] | 4 studies · 5231 participants | Moderate |
Transcervical vs transabdominal chorionic villus sampling Laboratory failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 2.23 [0.69, 7.22] | 1 study · 1194 participants | Low |
Transcervical vs transabdominal chorionic villus sampling Known false negative after birth · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Transcervical vs transabdominal chorionic villus sampling Delivery before 33 weeks · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Transcervical vs transabdominal chorionic villus sampling Anomalies (all recorded) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.68 [0.41, 1.12] | 2 studies · 3622 participants | Low |
Second trimester amniocentesis vs control Sampling failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Early amniocentesis vs transabdominal chorionic villus sampling All known pregnancy loss (including termination of pregnancy) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.15 [0.86, 1.54] | 4 studies · 5491 participants | Low |
Early amniocentesis vs transabdominal chorionic villus sampling Spontaneous miscarriage · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.73 [1.15, 2.6] | 4 studies · 5491 participants | Moderate |
Early amniocentesis vs transabdominal chorionic villus sampling Sampling failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.58 [0.24, 1.38] | 4 studies · 5566 participants | Low |
Early amniocentesis vs transabdominal chorionic villus sampling Laboratory failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.74 [0.34, 1.63] | 4 studies · 5566 participants | Low |
Early amniocentesis vs transabdominal chorionic villus sampling Known false negative after birth · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | 1 study · 555 participants | Low |
Early amniocentesis vs transabdominal chorionic villus sampling Delivery before 33 weeks · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.5 [0.09, 2.73] | 1 study · 1121 participants | Low |
Early amniocentesis vs transabdominal chorionic villus sampling Anomalies (all recorded) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.14 [0.57, 2.3] | 4 studies · 5305 participants | Very low |
Second trimester amniocentesis vs control Laboratory failure · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 27.02 [1.61, 454.31] | 1 study · 4606 participants | High |
Second trimester amniocentesis vs control Known false negative after birth · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Second trimester amniocentesis vs control Delivery before 33 weeks · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | no estimate extracted | NR | No studies |
Second trimester amniocentesis vs control Anomalies (all recorded) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 0.93 [0.62, 1.39] | 1 study · 4507 participants | Moderate |
Early vs second trimester amniocentesis All known pregnancy loss (including termination of pregnancy) · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.29 [1.03, 1.61] | 1 study · 4334 participants | High |
Early vs second trimester amniocentesis Spontaneous miscarriage · prenatal diagnosis Amniocentesis and chorionic villus sampling for prenatal diagnosis (2017) · Cochrane | RR 1.41 [1, 1.98] | 1 study · 4334 participants | Moderate |
Continuous support vs usual care (all trials) Spontaneous vaginal birth · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | RR 1.08 [1.04, 1.12] | 21 studies · 14369 participants | Low |
Continuous support vs usual care (all trials) Negative rating of/negative feelings about birth experience · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | RR 0.69 [0.59, 0.79] | 11 studies · 11133 participants | Low |
Continuous support vs usual care (all trials) Postpartum depression · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | no estimate extracted | 2 studies · 5716 participants | Low |
Continuous support vs usual care (all trials) Admission to special care nursery · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | RR 0.97 [0.76, 1.25] | 7 studies · 8897 participants | Low |
Continuous support vs usual care (all trials) Exclusive or any breastfeeding at any time point, as defined by trial authors · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | RR 1.05 [0.96, 1.16] | 4 studies · 5584 participants | Low |
Continuous support vs usual care (all trials) Labour length · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | no estimate extracted | 13 studies · 5429 participants | Low |
Continuous support vs usual care (all trials) Caesarean birth · women during childbirth Continuous support for women during childbirth (2017) · Cochrane | RR 0.75 [0.64, 0.88] | 24 studies · 15347 participants | Low |
Planned early birth vs expectant management Neonatal infection/sepsis · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 0.93 [0.66, 1.3] | 12 studies · 3628 participants | Moderate |
Planned early birth vs expectant management Neonatal respiratory distress syndrome · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 1.26 [1.05, 1.53] | 12 studies · 3622 participants | High |
Planned early birth vs expectant management Need for ventilation · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 1.27 [1.02, 1.58] | 7 studies · 2895 participants | High |
Planned early birth vs expectant management Admission to neonatal intensive care · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 1.16 [1.08, 1.24] | 4 studies · 2691 participants | Moderate |
Planned early birth vs expectant management Caesarean section · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 1.26 [1.11, 1.44] | 12 studies · 3620 participants | High |
Planned early birth vs expectant management Chorioamnionitis · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | RR 0.5 [0.26, 0.95] | 8 studies · 1358 participants | Moderate |
Planned early birth vs expectant management Length of hospital stay (maternal) · women with preterm prelabour rupture of membranes prior to 37 weeks' gestation Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior… (2017) · Cochrane | no estimate extracted | 6 studies · 2848 participants | Moderate |
Admission cardiotocography vs Intermittent auscultation (low‐risk women) Incidence of caesarean section · Low risk pregnant women. All of the women were in labour. Cardiotocography versus intermittent auscultation of fetal heart on admission to labour ward for assessment… (2017) · Cochrane | RR 1.2 [1, 1.44] | 4 studies · 11338 participants | Moderate |
Admission cardiotocography vs Intermittent auscultation (low‐risk women) Incidence of operative vaginal birth · Low risk pregnant women. All of the women were in labour. Cardiotocography versus intermittent auscultation of fetal heart on admission to labour ward for assessment… (2017) · Cochrane | RR 1.1 [0.95, 1.27] | 4 studies · 11338 participants | Low |