Comparison 1. Intentional endometrial injury vs no intervention or a sham procedure.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Live birth or ongoing pregnancy: primary analysis (low risk of bias only)	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected
1.1.1 Live birth	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected
1.2 Live birth or ongoing pregnancy: sensitivity analysis (all studies)	8	1522	Risk Ratio (M‐H, Random, 95% CI)	1.71 [1.32, 2.21]
1.2.1 Live birth	4	756	Risk Ratio (M‐H, Random, 95% CI)	1.64 [1.06, 2.52]
1.2.2 Ongoing pregnancy	4	766	Risk Ratio (M‐H, Random, 95% CI)	2.06 [1.41, 3.01]
1.3 Clinical pregnancy: sensitivity analysis (all studies)	19	3184	Risk Ratio (M‐H, Random, 95% CI)	2.02 [1.67, 2.45]
1.4 Miscarriage: primary analysis (low risk of bias only)	1		Risk Ratio (M‐H, Random, 95% CI)	Subtotals only
1.5 Miscarriage: sensitivity analysis (all studies)	14	2529	Risk Ratio (M‐H, Random, 95% CI)	1.29 [0.77, 2.17]
1.6 Multiple pregnancy: sensitivity analysis (all studies)	9	1378	Risk Ratio (M‐H, Random, 95% CI)	1.84 [0.68, 4.96]
1.7 Ectopic pregnancy: sensitivity analysis (all studies)	4	658	Risk Ratio (M‐H, Random, 95% CI)	1.66 [0.40, 6.91]