Table 3

Unadjusted and adjusted ORs for association of characteristics and spontaneous perineal trauma in women with a singleton vaginal delivery
Characteristics Unadjusted Adjusted
OR (95% CI) OR (95% CI)
Nulliparity 1.0 1.0
Multiparity 1.05 (0.90, 1.23) 0.42 (0.32, 0.56)*
Community (FMU or home) 1.0 1.0
Hospital 0.92 (0.74, 1.15) 1.48 (1.01, 2.17)*
Age group (years)1
< 21 1.0 1.0
21–30 1.10 (0.78, 1.56) NE
31–40 1.34 (0.81, 1.61) NE
> 40 1.03 (0.59, 1.79) NE
Birthing pool2 1.39 (1.05, 1.86)* 1.10 (0.72, 1.66)
Epidural3 0.69 (0.58, 0.81)* 0.90 (0.67, 1.20)
Spontaneous (non-operative) delivery 1.0 1.0
Ventouse 0.40 (0.31, 0.52)* 1.86 (1.00, 3.48)
Forceps 0.18 (0.13, 0.24)* 2.61 (1.22, 5.56)*
Directed pushing4 0.79 (0.67, 0.93)* 1.12 (0.88, 1.44)
Delivery position lying down 1.0 1.0
Delivery position upright 1.85 (1.56, 2.19)* 1.20 (0.93, 1.56)
Perineum touched5 0.91 (0.75, 1.11)* 1.09 (0.81, 1.47)
Delivery technique hands on either or both perineum and head 1.0 1.0
Delivery technique off/off 1.31 (1.08, 1.60)* 0.78 (0.61, 1.00)
Occipito posterior or Occipito transverse 1.0 1.0
Occipital anterior 2.03 (1.42, 2.91)* 1.28 (0.73, 2.24)
Duration 2nd stage (log mins) 0.96 (0.90, 1.02)* 1.45 (1.28, 1.63)*
Episiotomy6 0.03 (0.02, 0.04) * 0.01 (0.00, 0.01) *
Dystocia7 0.74 (0.39, 1.41) 0.28 (0.09, 0.93) *
Birth weight (grams) 1.00 (1.00, 1.00)* 1.001 (1.000, 1.001)*

Reference category: * = statistically significant (p < 0.05); 1 = age <21 years; 2 = birthing pool not used; 3 = epidural not used; 4 = undirected pushing; 5 = perineum not touched; 6 = no episiotomy; 7 = no shoulder dystocia; NE = not estimated.

Smith et al.

Smith et al. BMC Pregnancy and Childbirth 2013 13:59   doi:10.1186/1471-2393-13-59

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