Table 3 Multivariate analysis with the dependent variable as the log transform of gravimetric blood loss

Effect size (η _p ² )

Sig

Effect size (η _p ² )

Sig

Intercept

.060

.000

0.232

0.000

 Maternal Age

.003

.331

 BMI

.001

.487

Baby Birth Weight

.017

.013

0.018

0.009

 Gestation

.006

.132

 (Ln) Length First Stage

.006

.163

0.009

0.070

 (Ln) Length Second Stage

.001

.537

 (Ln) Length Third Stage

.000

.768

 Any Smoking (yes/no)

.002

.395

 Previous Birth (yes/no)

.000

.841

Perineal Injury 2nd-4th grade (yes/no)

.054

.000

0.050

0.000

 Episiotomy (yes/no)

.001

.510

 Labour onset induced (yes/no)

.004

.210

Labour complications (yes/no)

.016

.017

0.018

0.008

 Pharmacological Pain Relief (yes/no)

.001

.600

 Maternal position (upright, non-upright, other)

.008

.240

Baby separated from mother within first hour of birth (yes/no)

.008

.101

0.010

0.046

Placental birth management (active/mixed active/physiological)

.031

.004

0.033

0.002

 Oxytocic after cord clamping (yes/no)

.015

.066

0.013

0.086

 Signs of separation: cord lengthening (yes/no)

.002

.370

Signs of separation: gush of blood or clot (yes/no)

.044

.000

0.044

0.000

 Signs of separation: uterus risen above umbilicus (yes/no)

.004

.208

 Signs of separation: maternal urge to push (yes/no)

.003

.274

Adjusted R Squared

0.165

0.167