Table 5 Factors correlated with postpartum haemorrhage (multivariable analysis)

Gestational diabetes mellitus

No

Class A1

Class A2

Pre-existing diabetes mellitus

Ref.

1.51 (1.05, 2.17)

1.42 (0.33, 6.13)

–

0.026

0.639

–

Ref.

1.46 (1.01, 2.11)

1.69 (0.38, 7.45)

–

0.045^*

0.491

–

Hypertension (HT)

No

Gestational HT/transient

Severe pre-eclampsia

Pre-existing HT

Ref.

1.54 (0.96, 2.47)

1.86 (0.42, 8.21)

–

0.072

0.415

–

Ref.

1.28 (0.78, 2.09)

1.62 (0.35, 7.46)

–

0.325

0.533

–

Surgeon

Resident and Fellow

Staff

Medical students and midwives

Ref.

0.50 (0.24, 1.03)

1.01 (0.59, 1.70)

0.058

0.991

Ref.

0.58 (0.28, 1.20)

0.90 (0.52, 1.57)

0.144

0.720

Vaginal delivery

Spontaneous

Vacuum-assisted extraction

Forceps-assisted extraction

Breech delivery

Ref.

1.99 (1.30, 3.04)

6.77 (2.02, 22.7)

–

0.002

0.002

–

Ref.

0.89 (0.32, 2.47)

5.11 (1.30, 20.1)

–

0.821

0.020^*

–

Underlying disease

1.57 (0.83, 2.98)

0.161

1.65 (0.86, 3.17)

0.136

Prolonged second stage of labour

3.09 (1.85, 5.18)

< 0.001

2.68 (1.09, 6.58)

0.032^*

Foetal distress

1.98 (1.20, 3.27)

0.006

1.32 (0.55, 3.16)

0.539

High maternal weight (71.4 ± 12.2 kg)

1.02 (1.01, 1.03)

< 0.001

1.02 (1.01, 1.03)

0.003^*

Neonatal birthweight (g)

Normal (2500–4000)

Low 1500–2499)

High (> 4000)

Ref.

0.79 (0.46, 1.38)

4.25 (1.79, 10.1)

0.416

0.001

Ref.

0.90 (0.51, 1.59)

3.02 (1.23, 7.43)

0.721

0.016^*