Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Miscarriage rates
Systematic review	180 women with unexplained recurrent miscarriage 4 RCTs in this analysis	Proportion of women who had a miscarriage 13/95 (14%) with human chorionic gonadotrophin 34/85 (40%) with placebo	RR 0.35 95% CI 0.20 to 0.63 Results may be unreliable owing to methodological weaknesses of the included RCTs; see further information on studies	Moderate effect size	human chorionic gonadotrophin