Comparison 1. Balloon (Foley or ATAD) versus vaginal prostaglandin E2: all women.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Vaginal delivery not achieved in 24 hours	7	1685	Risk Ratio (M‐H, Random, 95% CI)	1.01 [0.82, 1.26]
2 Uterine hyperstimulation with FHR changes	6	1966	Risk Ratio (M‐H, Fixed, 95% CI)	0.35 [0.18, 0.67]
3 Caesarean section	28	6619	Risk Ratio (M‐H, Fixed, 95% CI)	1.00 [0.92, 1.09]
4 Serious neonatal morbidity/perinatal death	8	2757	Risk Ratio (M‐H, Fixed, 95% CI)	0.48 [0.25, 0.93]
5 Serious maternal morbidity or death	4	1481	Risk Ratio (M‐H, Fixed, 95% CI)	0.20 [0.01, 4.12]
6 Oxytocin augmentation	16	4828	Risk Ratio (M‐H, Random, 95% CI)	1.54 [1.35, 1.76]
7 Uterine hyperstimulation without fetal heart rate changes	15	2444	Risk Ratio (M‐H, Random, 95% CI)	0.27 [0.11, 0.66]
8 Uterine rupture	2	1045	Risk Ratio (M‐H, Fixed, 95% CI)	0.20 [0.01, 4.12]
9 Epidural analgesia	8	2828	Risk Ratio (M‐H, Random, 95% CI)	1.14 [1.00, 1.29]
10 Instrumental vaginal delivery	16	4514	Risk Ratio (M‐H, Fixed, 95% CI)	0.93 [0.79, 1.09]
11 Meconium‐stained liquor	4	964	Risk Ratio (M‐H, Fixed, 95% CI)	0.89 [0.67, 1.19]
12 Apgar score < 7 at 5 minutes	14	4271	Risk Ratio (M‐H, Fixed, 95% CI)	0.74 [0.49, 1.14]
13 Neonatal intensive care unit admission	12	3647	Risk Ratio (M‐H, Fixed, 95% CI)	0.82 [0.65, 1.04]
14 Perinatal death	5	1036	Risk Ratio (M‐H, Fixed, 95% CI)	0.21 [0.01, 4.27]
15 Postpartum haemorrhage	8	2215	Risk Ratio (M‐H, Fixed, 95% CI)	0.82 [0.63, 1.06]
16 Women not satisfied	1	93	Risk Ratio (M‐H, Fixed, 95% CI)	0.61 [0.39, 0.97]
17 Maternal fever during labour	7	2362	Risk Ratio (M‐H, Fixed, 95% CI)	0.87 [0.65, 1.17]
18 Antibiotics during labour	1	330	Risk Ratio (M‐H, Fixed, 95% CI)	1.43 [0.89, 2.29]
19 Chorioamnionitis	1	376	Risk Ratio (M‐H, Fixed, 95% CI)	0.69 [0.32, 1.49]
20 Endometritis	2	706	Risk Ratio (M‐H, Fixed, 95% CI)	0.49 [0.19, 1.27]
21 Fetal distress	20	4753	Risk Ratio (M‐H, Fixed, 95% CI)	0.71 [0.60, 0.83]
22 Umbilical artery pH < 7.10	8	2675	Odds Ratio (M‐H, Fixed, 95% CI)	0.65 [0.44, 0.94]