Comparison 4. Betamimetic versus placebo/no treatment (preterm birth and hospital admissions).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Preterm birth within 24 hours	1	46	Risk Ratio (M‐H, Fixed, 95% CI)	0.67 [0.12, 3.62]
1.1 Terbutaline versus placebo/no treatment	1	46	Risk Ratio (M‐H, Fixed, 95% CI)	0.67 [0.12, 3.62]
2 Preterm birth within 48 hours	1	200	Risk Ratio (M‐H, Fixed, 95% CI)	0.78 [0.30, 2.01]
2.1 Terbutaline versus placebo/no treatment	1	200	Risk Ratio (M‐H, Fixed, 95% CI)	0.78 [0.30, 2.01]
3 Preterm birth within 1 week	2	295	Risk Ratio (M‐H, Fixed, 95% CI)	0.67 [0.40, 1.13]
3.1 Ritodrine versus placebo	1	95	Risk Ratio (M‐H, Fixed, 95% CI)	0.23 [0.03, 1.94]
3.2 Terbutaline versus placebo	1	200	Risk Ratio (M‐H, Fixed, 95% CI)	0.75 [0.44, 1.29]
4 Maternal antenatal readmission to hospital	4	335	Risk Ratio (M‐H, Fixed, 95% CI)	1.11 [0.76, 1.62]
4.1 Ritodrine versus placebo/no treatment	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	0.86 [0.50, 1.46]
4.2 Terbutaline versus placebo/no treatment	3	285	Risk Ratio (M‐H, Fixed, 95% CI)	1.27 [0.77, 2.10]