Comparison 4. Letrozole compared to laparoscopic ovarian drilling.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
4.1 Live birth rate	1		Odds Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.2 Clinical pregnancy rate	3	367	Odds Ratio (M‐H, Fixed, 95% CI)	1.47 [0.95, 2.28]
4.2.1 AI versus LOD	2	221	Odds Ratio (M‐H, Fixed, 95% CI)	1.69 [0.96, 2.97]
4.2.2 AI + metformin versus LOD	1	146	Odds Ratio (M‐H, Fixed, 95% CI)	1.20 [0.60, 2.39]
4.3 Miscarriage rate per woman	3	367	Odds Ratio (M‐H, Fixed, 95% CI)	0.87 [0.31, 2.44]
4.3.1 AI versus LOD	2	221	Odds Ratio (M‐H, Fixed, 95% CI)	0.58 [0.14, 2.50]
4.3.2 AI + metformin versus LOD	1	146	Odds Ratio (M‐H, Fixed, 95% CI)	1.35 [0.29, 6.27]
4.4 Miscarriage rate per pregnancy	3	122	Odds Ratio (M‐H, Fixed, 95% CI)	0.65 [0.22, 1.92]
4.4.1 AI versus LOD	2	73	Odds Ratio (M‐H, Fixed, 95% CI)	0.38 [0.08, 1.72]
4.4.2 AI + metformin versus LOD	1	49	Odds Ratio (M‐H, Fixed, 95% CI)	1.21 [0.24, 6.09]
4.5 Multiple pregnancy rate	1		Odds Ratio (M‐H, Fixed, 95% CI)	Subtotals only