Comparison 4. Any antihypertensive drug versus no antihypertensive drugs/placebo (subgrouped by use of placebo).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Severe hypertension	20	2558	Risk Ratio (M‐H, Fixed, 95% CI)	0.49 [0.40, 0.60]
1.1 Placebo	10	937	Risk Ratio (M‐H, Fixed, 95% CI)	0.50 [0.36, 0.69]
1.2 No placebo	10	1621	Risk Ratio (M‐H, Fixed, 95% CI)	0.48 [0.38, 0.62]
2 Proteinuria/pre‐eclampsia	23	2851	Risk Ratio (M‐H, Random, 95% CI)	0.92 [0.75, 1.14]
2.1 Placebo	10	869	Risk Ratio (M‐H, Random, 95% CI)	0.90 [0.65, 1.24]
2.2 No placebo	13	1982	Risk Ratio (M‐H, Random, 95% CI)	0.94 [0.69, 1.26]
3 Total reported fetal or neonatal death (including miscarriage)	28	3330	Risk Ratio (M‐H, Random, 95% CI)	0.73 [0.50, 1.05]
3.1 Placebo	11	1011	Risk Ratio (M‐H, Random, 95% CI)	0.72 [0.35, 1.47]
3.2 No placebo	17	2319	Risk Ratio (M‐H, Random, 95% CI)	0.73 [0.47, 1.13]
4 Small‐for‐gestational age	21	2686	Risk Ratio (M‐H, Random, 95% CI)	0.96 [0.78, 1.18]
4.1 Placebo	9	814	Risk Ratio (M‐H, Random, 95% CI)	0.94 [0.65, 1.35]
4.2 No placebo	12	1872	Risk Ratio (M‐H, Random, 95% CI)	0.98 [0.75, 1.29]
5 Preterm birth (< 37 weeks)	15	2141	Risk Ratio (M‐H, Random, 95% CI)	0.96 [0.83, 1.12]
5.1 Placebo	5	566	Risk Ratio (M‐H, Random, 95% CI)	0.85 [0.62, 1.17]
5.2 No placebo	10	1575	Risk Ratio (M‐H, Random, 95% CI)	1.00 [0.81, 1.23]