Summary of findings 1. Endometrial injury compared to control in women undergoing assisted reproductive techniques.
| Endometrial injury compared to control in women undergoing assisted reproductive techniques | ||||||
| Patient or population: women undergoing assisted reproductive techniques Setting: clinic Intervention: endometrial injury Comparison: control | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with control | Risk with Endometrial injury | |||||
| Live birth per woman randomised (studies at low risk of selection bias and other bias) | 273 per 1,000 | 296 per 1,000 (269 to 324) | OR 1.12 (0.98 to 1.28) | 4402 (8 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | |
| Live birth per woman randomised: sensitivity analysis (no high risk) | 254 per 1,000 | 278 per 1,000 (177 to 409) | OR 1.13 (0.63 to 2.03) | 229 (1 RCT) | ⊕⊕⊝⊝ LOW 2 3 | |
| Live birth per woman randomised: sensitivity analysis (including all studies) | Meta‐analysis not undertaken | ‐ | 7792 (29 RCTs) | ⊕⊝⊝⊝ VERY LOW 4 5 | ||
| Miscarriage per woman randomised (studies at low risk of selection bias and other bias) | 60 per 1,000 | 53 per 1,000 (42 to 68) | OR 0.88 (0.68 to 1.13) | 4402 (8 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | |
| Miscarriage per woman randomised: sensitivity analysis (no high risk) | 53 per 1,000 | 61 per 1,000 (21 to 166) | OR 1.17 (0.38 to 3.58) | 229 (1 RCT) | ⊕⊕⊝⊝ LOW 2 3 | |
| Miscarriage per woman randomised: sensitivity analysis (including all studies) | 54 per 1,000 | 56 per 1,000 (46 to 67) | OR 1.03 (0.85 to 1.25) | 8092 (30 RCTs) | ⊕⊕⊝⊝ LOW 4 | |
| Clinical pregnancy per woman randomised (studies at low risk of selection bias and other bias) | 323 per 1,000 | 340 per 1,000 (312 to 370) | OR 1.08 (0.95 to 1.23) | 4402 (8 RCTs) | ⊕⊕⊕⊝ MODERATE 1 | |
| Clinical pregnancy per woman randomised: sensitivity analysis (no high‐risk) | 307 per 1,000 | 339 per 1,000 (229 to 472) | OR 1.16 (0.67 to 2.02) | 229 (1 RCT) | ⊕⊕⊝⊝ LOW 2 3 | |
| Clinical pregnancy per woman randomised: sensitivity analysis (including all studies) | Meta‐analysis not undertaken | ‐ | 8786 (37 RCTs) | ⊕⊝⊝⊝ VERY LOW 4 5 | ||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; OR: Odds ratio; RCT: randomised controlled trial. | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate; the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate; the true effect is likely to be substantially different from the estimate of effect. | ||||||
1 Downgraded once for imprecision as the confidence intervals include appreciable benefit, no effect and harm
2 Downgraded once for indirectness as the trial was undertaken in women undergoing frozen embryo transfer cycles only
3 Downgraded once for imprecision as only one trial included and the confidence interval is wide
4 Downgraded twice for high risk of bias as the majority of included studies display very serious risk of bias
5 Downgraded once for inconsistency due to high statistical heterogeneity