Table 4 The percentage distributions of actual mode of deliveries following spontaneous and induced labours. The corresponding relative risk with 95 % confidence interval for belonging to each group when labour was induced

Primiparas (n=43 403)

n

%

n

%

RR

95% CI

 Vaginal delivery (both)

22 428

70.7

6 382

54.7

0.77

0.76 to 0.79

 Instrumental delivery

5 819

18.3

2 206

18.9

1.03

0.99 to 1.08

 Urgent CS

6 179

10.0

2 934

25.1

2.51

2.40 to 2.62

 Emergency CS

300

0.9

155

1.3

1.40

1.16 to 1.70

Multiparas (n=51 648)

n

%

n

%

RR

95% CI

 Vaginal delivery (both)

37 239

91.0

8 971

83.7

0.92

0.91 to 0.93

 Instrumental delivery

1 767

4.3

676

6.3

1.46

1.34 to 1.59

 Urgent CS

1 774

4.3

967

9.0

2.08

1.93 to 2.25

 Emergency CS

152

0.4

102

1.0

2.56

2.00 to 3.29