Comparison 4. Nitric oxide donors versus any calcium channel blocker.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Prolongation of pregnancy greater than 48 hours	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	0.97 [0.77, 1.21]
2 Headache	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	3.69 [0.87, 15.69]
3 Flushing	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	1.85 [0.18, 19.08]
4 Hypotension	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	0.31 [0.03, 2.76]
5 Nausea	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	0.62 [0.11, 3.37]
6 Tachycardia	1	50	Risk Ratio (M‐H, Fixed, 95% CI)	0.31 [0.01, 7.23]