Table 4 Mode of delivery and obstetric data among teenage women with singleton births in the period 1992–2010

Spontaneous onset delivery

1.23 (1.19-1.27)

1.17 (1.13-1.21)

1.00 (0.78-1.28)

0.92 (0.72-1.18)

1.27 (1.17-1.38)

1.18 (1.09-1.28)

1.22 (1.17-1.27)

1.17 (1.13-1.22)

Induced delivery

0.90 (0.86-0.93)

0.92 (0.88-0.96)

0.93 (0.68-1.29)

0.95 (0.69-1.32)

0.86 (0.78-0.95)

0.91 (0.82-1.00)

0.90 (0.86-0.95)

0.92 (0.88-0.97)

Normal vaginal delivery

1.29 (1.25-1.33)

1.70 (1.64-1.75)

1.18 (0.92-1.51)

1.61 (1.26-2.06)

1.34 (1.25-1.45)

1.80 (1.66-1.94)

1.28 (1.23-1.33)

1.67 (1.61-1.74)

Forceps

0.88 (0.73-1.06)

0.56 (0.46-0.68)

0.99 (0.25-3.98)

0.67 (0.17-2.68)

0.57 (0.33-0.98)

0.34 (0.19-0.60)

0.95 (0.78-1.17)

0.61 (0.50-0.76)

Vacuum extraction

0.91 (0.87-0.95)

0.59 (0.56-0.62)

0.86 (0.59-1.25)

0.50 (0.34-0.74)

0.88 (0.78-0.98)

0.54 (0.49-0.61)

0.92 (0.87-0.97)

0.60 (0.57-0.63)

CS, all

0.71 (0.69-0.75)

0.61 (0.58-0.64)

0.85 (0.63-1.16)

0.65 (0.47-0.88)

0.70 (0.63-0.77)

0.58 (0.52-0.64)

0.72 (0.68-0.75)

0.61 (0.58-0.64)

CS elective 1999-2010^‡

0.55 (0.50-0.61)

0.57 (0.51-0.63)

1.74 (1.11-2.73)

1.54 (0.96-2.48)

0.52 (0.41-0.66)

0.52 (0.41-0.67)

0.54 (0.48-0.60)

0.56 (0.50-0.63)

CS acute 1999-2010^‡

0.79 (0.73-0.84)

0.62 (0.58-0.67)

0.73 (0.42-1.27)

0.47 (0.27-0.83)

0.83 (0.72-1.07)

0.64 (0.55-0.75)

0.78 (0.72-0.84)

0.62 (0.57-0.67)

GA < 28 weeks

1.93 (1.57-2.37)

1.61 (1.31-2.00)

4.86 (1.81-13.01)

4.44 (1.66-11.92)

2.65 (1.78-3.93)

2.23 (1.48-3.35)

1.71 (1.35-2.17)

1.42 (1.11-1.83)

GA < 32 weeks

1.61 (1.43-1.81)

1.37 (1.21-1.55)

2.46 (1.17-5.20)

2.25 (1.06-4.74)

2.25 (1.78-2.84)

1.90 (1.50-2.41)

1.46 (1.26-1.66)

1.24 (1.07-1.43)

GA < 37 weeks

1.33 (1.27-1.40)

1.14 (1.08-1.20)

2.57 (1.94-3.42)

2.15 (1.60-2.87)

1.53 (1.38-1.70)

1.28 (1.15-1.42)

1.26 (1.20-1.33)

1.09 (1.03-1.15)

GA 37 – 41 weeks

0.91 (0.88-0.95)

1.03 (0.99 -1.06)

0.62 (0.49-0.79)

0.71 (0.55-0.90)

0.83 (0.77-0.89)

0.93 (0.86-1.01)

0.94 (0.91-0.98)

1.06 (1.02-1.10)

GA ≥42 weeks

0.92 (0.88-0.97)

0.85 (0.81-0.89)

0.87 (0.60-1.27)

0.84 (0.57-1.22)

0.96 (0.87-1.07)

0.91 (0.81-1.01)

0.91 (0.87-0.96)

0.84 (0.80-0.89)

Epidural analgesia^¥

1.76 (1.72-1.81)

1.08 (1.05-1.11)

1.80 (1.49-2.18)

1.00 (0.82-1.22)

1.91 (1.81-2.02)

1.10 (1.03-1.16)

1.73 (1.68-1.78)

1.08 (1.05-1.11)

Perineal rupture grade 1-2^¥

0.60 (0.58-0.62)

0.52 (0.50-0.54)

0.66 (0.51-0.86)

0.48 (0.37-0.64)

0.56 (0.52-0.61)

0.47 (0.43-0.52)

0.61 (0.58-0.63)

0.53 (0.51-0.55)

Perineal rupture grade 3-4^¥

0.57 (0.51-0.64)

0.43 (0.38-0.49)

0.52 (0.19-1.39)

0.34 (0.13-0.91)

0.62 (0.47-0.81)

0.45 (0.34-0.59)

0.56 (0.49-0.64)

0.43 (0.37-0.49)

Preeclampsia

1.12 (1.03-1,23)

0.94 (0.86-1.03)

1.64 (0.93-2.91)

1.23 (0.67-2.25)

1.06 (0.86-1.31)

0.92 (0.74-1.14)

1.13 (1.02-1.24)

0.94 (0.85-1.04)

Abruptio placentae

1.31 (1.11-1.55)

1.19 (0.99-1.41)

0.57 (0.08-4.05)

0.59 (0.08-4.17)

1.46 (1.01-2.10)

1.34 (0.93-1.94)

1.29 (1.07-1.56)

1.17 (0.96-1.41)

Placenta praevia

0.34 (0.21-0.55)

0.37 (0.23-0.59)

2.53 (0.63-10.15)

2.72 (0.68-10.93)

0.11 (0.02-0.79)

0.12 (0.02-0.83)

0.35 (0.21-0.60)

0.38 (0.22-0.64)

PPH > 1000 ml (VD)

0.73 (0.67-0.79)

0.70 (0.64-0.76)

0.70 (0.37-1.31)

0.61 (0.33-1.15)

0.76 (0.63-0.91)

0.71 (0.60-0.85)

0.72 (0.66-0.79)

0.70 (0.64-0.76)

PPH > 1000 ml (CS)

0.93 (0.63-1.36)

0.98 (0.66-1.44)

N/A

N/A

1.74 (0.90-3.38)

1.71 (0.88-3.33)

0.77 (0.48-1.23)

0.75 (0.47-1.20)