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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.
2,653 questions in 194 reviews · Gynaecology and Fertility
current versionsNo studies 531 · 20%Ungraded 76 · 2.9%Very low 826 · 31.1%Low 855 · 32.2%Moderate 341 · 12.9%High 24 · 0.9%
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 |
|---|---|---|---|
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Endometrial hyperplasia · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 0.13 [0.03, 0.67] | 4 studies · 417 participants | Moderate |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Endometrial cancer · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | no estimate extracted | 2 studies · 154 participants | Moderate |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Fibroids · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 0.48 [0.16, 1.46] | 3 studies · 314 participants | Moderate |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Abnormal vaginal bleeding or spotting · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 7.26 [3.37, 15.66] | 3 studies · 376 participants | Moderate |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Breast cancer recurrence · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 1.74 [0.64, 4.74] | 2 studies · 154 participants | Moderate |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Breast cancer‐related death · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 1.02 [0.36, 2.84] | 3 studies · 277 participants | Moderate |
High vs low or no hyaluronic acid Live birth rate ‐ high vs low or no hyaluronic acid · couples undergoing embryo transfer Hyaluronic acid in embryo transfer media for assisted reproductive technologies (2020) · Cochrane | RR 1.21 [1.11, 1.31] | 10 studies · 4066 participants | Moderate |
High vs low or no hyaluronic acid Miscarriage rate · couples undergoing embryo transfer Hyaluronic acid in embryo transfer media for assisted reproductive technologies (2020) · Cochrane | RR 0.82 [0.67, 1] | 7 studies · 3091 participants | Low |
High vs low or no hyaluronic acid Clinical pregnancy rate ‐ high vs low or no hyaluronic acid · couples undergoing embryo transfer Hyaluronic acid in embryo transfer media for assisted reproductive technologies (2020) · Cochrane | RR 1.16 [1.09, 1.23] | 17 studies · 5247 participants | Moderate |
High vs low or no hyaluronic acid Multiple pregnancy rate · couples undergoing embryo transfer Hyaluronic acid in embryo transfer media for assisted reproductive technologies (2020) · Cochrane | RR 1.45 [1.24, 1.7] | 7 studies · 3337 participants | Moderate |
High vs low or no hyaluronic acid Adverse event rate · couples undergoing embryo transfer Hyaluronic acid in embryo transfer media for assisted reproductive technologies (2020) · Cochrane | RR 0.86 [0.4, 1.84] | 3 studies · 1487 participants | Low |
Antioxidant(s) vs placebo or no treatment/standard treatment Live birth; antioxidants vs placebo or no treatment/standard treatment (natural conceptions and undergoing fertility treatments)№ of participants: 1227(13 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.81 [1.36, 2.43] | NR | Very low |
Intervention NR Adverse events ‐ Miscarriage№ of participants: 304(3 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.54 [0.42, 5.67] | NR | Low |
Intervention NR Adverse events ‐ Multiple pregnancy · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Adverse events ‐ Gastrointestinal disturbances · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Adverse events ‐ Ectopic pregnancy Melatonin lower dose versus melatonin higher dose№ of participants: 120(1 RCT) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | no estimate extracted | NR | Very low |
Antioxidant(s) vs placebo or no treatment/standard treatment Clinical pregnancy; antioxidants vs placebo or no treatment/standard treatment (natural conceptions and undergoing fertility treatments)№ of participants: 5165(35 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.65 [1.43, 1.89] | NR | Low |
Antioxidant(s) vs placebo or no treatment/standard treatment Adverse events ‐ Miscarriage№ of participants: 3229(24 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.13 [0.82, 1.55] | NR | Low |
Antioxidant(s) vs placebo or no treatment/standard treatment Adverse events ‐ Multiple pregnancy№ of participants: 1886(9 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1 [0.63, 1.56] | NR | Low |
Antioxidant(s) vs placebo or no treatment/standard treatment Adverse events ‐ Gastrointestinal disturbances№ of participants: 343(3 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.55 [0.47, 5.1] | NR | Low |
Antioxidant(s) vs placebo or no treatment/standard treatment Adverse events ‐ Ectopic pregnancy№ of participants: 404(4 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 1.4 [0.27, 7.2] | NR | Low |
Intervention NR Live birth; type of antioxidant (natural conceptions and undergoing fertility treatments) ‐ Melatonin lower dose versus melatonin higher dose№ of participants: 140(2 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 0.94 [0.41, 2.15] | NR | Low |
Intervention NR Clinical pregnancy; type of antioxidant (natural conceptions and undergoing fertility treatments) ‐ N‐acetylcysteine versus L‐carnitine№ of participants: 164(1 RCT) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 0.81 [0.33, 2] | NR | Very low |
Intervention NR Clinical pregnancy; type of antioxidant (natural conceptions and undergoing fertility treatments) ‐ Melatonin lower dose versus melatonin higher dose№ of participants: 140(2 RCTs) · women with subfertility Antioxidants for female subfertility (2020) · Cochrane | OR 0.94 [0.41, 2.15] | NR | Low |
Levonorgestrel‐releasing intrauterine device vs low dose combined oral contraceptive Uterine fibroid‐related symptoms (change in abnormal uterine bleeding, measured at 12 months, with the alkaline hematin test) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 44 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs oral progestogen (norethisterone acetate) Adverse events (spotting at 3 and 6 months) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 45 participants | Very low |
Oral progestogen (dienogest, desogestrel) vs goserelin acetate Uterine fibroid‐related symptoms (duration of uterine bleeding, measured at 12 weeks; lower = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 14 participants | Very low |
Oral progestogen (dienogest, desogestrel) vs goserelin acetate Uterine fibroid‐related symptoms (abnormal uterine bleeding, measured at 12 weeks, with the pictorial blood assessment chart (PBAC); lower = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 14 participants | Very low |
Oral progestogen (dienogest, desogestrel) vs goserelin acetate Fibroid size · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral progestogen (dienogest, desogestrel) vs goserelin acetate Adverse events (vasomotor symptoms (e.g. hot flashes) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 14 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs low dose combined oral contraceptive Uterine fibroid‐related symptoms (change in abnormal uterine bleeding, measured at 12 months, with the pictorial blood assessment chart (PBAC)) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 44 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs low dose combined oral contraceptive Uterine fibroid‐related symptoms (haemoglobin level, at 12 months; higher = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 44 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs low dose combined oral contraceptive Fibroid size (percentage of change, at 12 months; higher = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 44 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs low dose combined oral contraceptive Adverse events · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | NR | No studies |
Levonorgestrel‐releasing intrauterine device vs oral progestogen (norethisterone acetate) Uterine fibroid‐related symptoms (change in abnormal uterine bleeding, measured from baseline to 6 months, with a visual bleeding score (VBS); lower = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 48 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs oral progestogen (norethisterone acetate) Uterine fibroid‐related symptoms (change in haemoglobin level, from baseline to 3 months; higher = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 48 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs oral progestogen (norethisterone acetate) Uterine fibroid‐related symptoms (change in haemoglobin level, from baseline to 6 months; higher = better) · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | 1 study · 45 participants | Very low |
Levonorgestrel‐releasing intrauterine device vs oral progestogen (norethisterone acetate) Fibroid size · women with uterine fibroids Progestogens or progestogen‐releasing intrauterine systems for uterine fibroids (other than preoperative… (2020) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Live birth per allocated couple · couples undergoing assisted reproduction treatment Regular (ICSI) versus ultra‐high magnification (IMSI) sperm selection for assisted reproduction (2020) · Cochrane | RR 1.11 [0.89, 1.39] | 5 studies · 929 participants | Very low |
Intervention NR Miscarriage per allocated couple · couples undergoing assisted reproduction treatment Regular (ICSI) versus ultra‐high magnification (IMSI) sperm selection for assisted reproduction (2020) · Cochrane | RR 1.07 [0.78, 1.48] | 10 studies · 2297 participants | Very low |
Intervention NR Miscarriage per clinical pregnancy · couples undergoing assisted reproduction treatment Regular (ICSI) versus ultra‐high magnification (IMSI) sperm selection for assisted reproduction (2020) · Cochrane | RR 0.9 [0.68, 1.2] | 10 studies · 783 participants | Very low |
Intervention NR Clinical pregnancy per allocated couple · couples undergoing assisted reproduction treatment Regular (ICSI) versus ultra‐high magnification (IMSI) sperm selection for assisted reproduction (2020) · Cochrane | RR 1.23 [1.11, 1.37] | 13 studies · 2775 participants | Very low |
Intervention NR Congenital abnormalities per live birth · couples undergoing assisted reproduction treatment Regular (ICSI) versus ultra‐high magnification (IMSI) sperm selection for assisted reproduction (2020) · Cochrane | no estimate extracted | NR | No studies |
Laparoscopic treatment vs diagnostic laparoscopy Overall pain scores unclear measurement instrument (6 months) · women with endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 16 participants | Very low |
Laparoscopic treatment vs diagnostic laparoscopy Adverse events: conversion to laparotomy · women with endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 341 participants | Low |
Laparoscopic ablation and uterine nerve transaction vs diagnostic laparoscopy Adverse events · endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | OR 0.33 [0.01, 8.32] | 1 study · 141 participants | Low |
Laparoscopic ablation vs laparoscopic excision Overall pain scores (reduction in VAS at 12 months) · endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 103 participants | Very low |
Helium thermal coagulator vs electrodiathermy Quality of life (9 months) – EHP‐30 pain · endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 119 participants | Very low |
Helium thermal coagulator vs electrodiathermy Quality of life (9 months) – EHP‐30 control and powerlessness · endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 119 participants | Very low |
Helium thermal coagulator vs electrodiathermy Quality of life (9 months) – EHP‐30 emotional well‐being · endometriosis Laparoscopic surgery for endometriosis (2020) · Cochrane | no estimate extracted | 1 study · 119 participants | Very low |