Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Nausea
RCT	120 women, 5.5 to 18.0 weeks' gestation In review	Nausea severity scores each of the four treatment days with ginger 125 mg in oral capsules taken four times daily for 4 days with placebo Absolute results reported graphically	Reported as significant P value not reported	Effect size not calculated	ginger
Vomiting
RCT	70 women, over 17 weeks' gestation In review	Proportion of women with vomiting 4 days 12/32 (38%) with ginger 250 mg in oral capsules taken four times daily 23/35 (66%) with placebo	RR 0.57 95% CI 0.34 to 0.95 NNT 4 95% CI 2 to 12	Small effect size	ginger
RCT	26 women, <13 weeks' gestation In review	Proportion of women who stopped vomiting 6 days 8/12 (67%) with ginger syrup (15 mL containing ginger 250 mg taken four times daily) 2/10 (20%) with placebo	RR 0.42 95% CI 0.18 to 0.98	Moderate effect size	ginger
RCT	120 women, 5.5 to 18.0 weeks' gestation In review	Dry retching first 2 days of treatment with ginger 125 mg in oral capsules taken four times daily for 4 days with placebo Absolute results not reported	Reported as significant P value not reported	Effect size not calculated	ginger
RCT	120 women, 5.5 to 18.0 weeks' gestation In review	Episodes of vomiting with ginger 125 mg in oral capsules taken four times daily for 4 days with placebo Absolute results not reported	Reported as not significant P value not reported		Not significant
Symptom improvement
RCT	70 women, over 17 weeks' gestation In review	Proportion of women with improved symptoms (non-specifically described) 7 days 28/32 (88%) with ginger 250 mg in oral capsules taken four times daily 10/35 (29%) with placebo	RR 0.18 95% CI 0.07 to 0.45	Large effect size	ginger