Comparison 4. Routine high‐dose calcium supplementation in pregnancy by baseline dietary calcium and study sample size (not prespecified).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Pre‐eclampsia	13	15730	Risk Ratio (M‐H, Random, 95% CI)	0.45 [0.31, 0.65]
1.1 Adequate calcium/small study	2	230	Risk Ratio (M‐H, Random, 95% CI)	0.26 [0.04, 1.50]
1.2 Adequate calcium/large study	2	4792	Risk Ratio (M‐H, Random, 95% CI)	0.70 [0.33, 1.46]
1.3 Low calcium/small study	5	675	Risk Ratio (M‐H, Random, 95% CI)	0.21 [0.12, 0.38]
1.4 Low calcium/large study	3	10003	Risk Ratio (M‐H, Random, 95% CI)	0.63 [0.35, 1.14]
1.5 Dietary calcium not specified	1	30	Risk Ratio (M‐H, Random, 95% CI)	0.14 [0.02, 1.02]