Table 1 Characteristics and delivery interventions (%) among the primiparous (n = 73,813) and multiparous women (n = 94,824) with singleton vaginal delivery in University Hospitals between 1997 and 2007 in Finland (Chi Square test/Kruskall Wallis test).

PRIMIPAROUS,

n = 73, 813

19, 185

12, 486

17, 749

15, 974

8, 419

Obstetric anal sphincter injuries (OASIS), n (%)

147 (0.8)

127 (1.0)

193 (1.1)

343 (2.1)

56 (0.7)

≤0.001

1.2

Birth weight >4,000 g

13.2

12.6

13.0

13.4

11.7

0.002

12.9

Mean (± SD) length of active second stage of birth (min)

34 ± 31

32 ± 28

92 ± 76

74 ± 61

21 ± 18

≤0.001

45 ± 48

Episiotomy

75.5

64.2

59.2

51.1

49.4

≤0.001

61.4

Vacuum assistance

15.3

15.8

15.9

15.4

10.6

≤0.001

15.0

Amniotomy

49.8

55.2

48.8

31.2

42.4

≤0.001

45.6

Augmentation with oxytocin

75.5

65.2

49.7

53.8

37.7

≤0.001

58.6

Epidural analgesia

62.7

65.7

64.3

78.6

73.7

≤0.001

68.3

Paracervical block

29

24.1

1.0

6.3

10.7

≤0.001

14.4

*Caesarean section

17.7

21.4

31.4

19.0

23.0

≤0.001

22.9

MULTIPAROUS,

n = 94, 824

23, 746

21, 291

20, 628

18, 032

11, 127

OASIS, n (%)

33 (0.1)

30 (0.1)

52 (0.3)

61 (0.3)

13 (0.1)

≤0.001

0.2

Birth weight >4000 g

24.3

22.3

21.7

24.0

22.2

≤0.001

23.0

Mean (± SD)length of active second stage of birth (min)

11 ± 13

9 ± 12

36 ± 44

21 ± 28

11 ± 11

≤0.001

13 ± 20

Episiotomy

15.2

8.6

20.4

6.5

10.3

≤0.001

12.6

Vacuum assistance

2.5

2.0

2.6

2.1

1.9

≤0.001

2.3

Amniotomy

53.6

60.0

52.3

34.9

43.9

≤0.001

50.1

Augmentation with oxytocin

37.6

35.1

33.8

23.3

20.5

≤0.001

31.5

Epidural analgesia

19.6

14.9

47.5

34.1

26.8

≤0.001

28.2

Paracervical block

44.8

41.6

2.8

25.8

26.2

≤0.001

29.2

*Caesarean section

8.0

9.5

15.7

8.8

12.1

≤0.001

10.7