Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Spontaneous pregnancy rate
RCT 3-armed trial	137 men (107 with primary infertility and 30 with secondary infertility, all with varicocele)	Proportion of men whose partners became pregnant 13/34 (38%) with Ivanissevich technique of ligation 7/34 (21%) with embolisation	P <0.05	Effect size not calculated	surgical ligation
RCT 3-armed trial	137 men (107 with primary infertility and 30 with secondary infertility, all with varicocele)	Proportion of men whose partners became pregnant 9/35 (26%) with Bernardi technique of ligation 7/34 (21%) with embolisation	Significance not assessed
RCT 3-armed trial	119 men with primary and secondary infertility	Proportion of men whose partners became pregnant 2 years 16/55 (29%) with Palomo technique of ligation 7/28 (25%) with Bernardi technique of ligation 10/36 (28%) with transcatheter embolisation	Difference among groups reported as not significant P value not reported		Not significant
RCT	71 infertile men with varicocele	Proportion of men whose partners became pregnant 12 months 11/38 (29%) with surgical ligation 11/33 (33%) with embolisation	P >0.05		Not significant