Comparison 1. Routine ultrasound > 24 weeks vs no/concealed/selective ultrasound > 24 weeks.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Antenatal admission	4	5396	Risk Ratio (M-H, Random, 95% CI)	1.07 [0.80, 1.43]
2 Number of days in hospital (mean, standard deviation (SD))	1	877	Mean Difference (IV, Fixed, 95% CI)	0.10 [0.07, 0.13]
3 CTG (cardiotocograph)	1	2000	Risk Ratio (M-H, Fixed, 95% CI)	1.02 [0.97, 1.06]
4 Further ultrasound scan/s	2	2536	Risk Ratio (M-H, Random, 95% CI)	0.91 [0.43, 1.89]
5 Induction of labour	6	22663	Risk Ratio (M-H, Random, 95% CI)	0.93 [0.81, 1.07]
6 Instrumental delivery	4	5884	Risk Ratio (M-H, Fixed, 95% CI)	1.04 [0.92, 1.18]
7 Caesarean section	5	21035	Risk Ratio (M-H, Fixed, 95% CI)	1.06 [1.00, 1.13]
8 Elective caesarean section	4	5884	Risk Ratio (M-H, Fixed, 95% CI)	1.09 [0.89, 1.34]
9 Emergency caesarean section	4	5884	Risk Ratio (M-H, Fixed, 95% CI)	1.11 [0.92, 1.33]
10 Preterm delivery < 37 weeks’ gestation	2	17151	Risk Ratio (M-H, Fixed, 95% CI)	0.96 [0.85, 1.08]
11 Post-term delivery >42 weeks’ gestation	2	17151	Risk Ratio (M-H, Fixed, 95% CI)	0.69 [0.59, 0.81]
12 Gestation at delivery (mean, SD)	2	2877	Mean Difference (IV, Fixed, 95% CI)	−0.16 [−0.26, −0.06]
13 Birthweight (mean, SD)	4	19710	Mean Difference (IV, Fixed, 95% CI)	−0.47 [−15.49, 14.54].
14 Birthweight < 10th centile	4	20293	Risk Ratio (M-H, Random, 95% CI)	0.98 [0.74, 1.28]
15 Birthweight < 5th centile	2	2404	Risk Ratio (M-H, Fixed, 95% CI)	1.18 [0.81, 1.74]
16 Low birthweight < 2.5 kg	3	4510	Risk Ratio (M-H, Fixed, 95% CI)	0.92 [0.71, 1.18]
17 Neonatal resuscitation	4	6533	Risk Ratio (M-H, Fixed, 95% CI)	0.95 [0.82, 1.10]
18 Neonatal ventilation	2	3004	Risk Ratio (M-H, Random, 95% CI)	0.64 [0.23, 1.77]
19 Admission to special care baby unit	4	6539	Risk Ratio (M-H, Fixed, 95% CI)	0.95 [0.79, 1.14]
20 Apgar score < 7 at 5 minutes	4	5889	Risk Ratio (M-H, Random, 95% CI)	0.89 [0.41, 1.93]
21 Moderate neonatal morbidity	1	15281	Risk Ratio (M-H, Fixed, 95% CI)	0.97 [0.81, 1.16]
22 Severe neonatal morbidity	1	15281	Risk Ratio (M-H, Fixed, 95% CI)	1.03 [0.78, 1.36]
23 Perinatal mortality	7	24276	Risk Ratio (M-H, Random, 95% CI)	0.94 [0.55, 1.61]
24 Stillbirths	5	21708	Risk Ratio (M-H, Random, 95% CI)	1.11 [0.29, 4.26]
25 Neonatal deaths	5	21708	Risk Ratio (M-H, Fixed, 95% CI)	1.04 [0.58, 1.85]
26 Perinatal mortality (excluding congenital abnormalities)	5	21734	Risk Ratio (M-H, Random, 95% CI)	0.88 [0.36, 2.17]
27 Stillbirths (excluding congenital abnormalities)	2	2902	Risk Ratio (M-H, Fixed, 95% CI)	0.05 [0.00, 0.90]
28 Neonatal deaths (excluding congenital abnormalities)	2	2902	Risk Ratio (M-H, Fixed, 95% CI)	1.99 [0.18, 21.96]
29 Perinatal mortality (twins)	3	314	Risk Ratio (M-H, Fixed, 95% CI)	0.63 [0.24, 1.66]