Table 3

Unadjusted and adjusted ORs expressing the change per year in the risk of birth trauma by mode of delivery among singleton infants, Washington State, USA, 2004–2013

Severe birth traumaMode of delivery
Spontaneous vaginal deliveryForceps deliveryVacuum deliveryCaesarean delivery with labour
OR
(95% CI)		AOR*
(95% CI)		OR
(95% CI)		AOR*
(95% CI)		OR
(95% CI)		AOR*
(95% CI)		OR
(95% CI)		AOR*
(95% CI)
Brain injury0.99
(0.93 to 1.05)		0.99
(0.93 to 1.05)		1.09
(0.90 to 1.31)		1.08
(0.90 to 1.30)		1.04
(0.96 to 1.11)		1.04
(0.97 to 1.13)		1.04
(0.95 to 1.14)		1.06
(0.96 to 1.16)
Fractures0.96
(0.94 to 0.98)		0.95
(0.94 to 0.97)		0.94
(0.82 to 1.07)		0.95
(0.83 to 1.08)		1.02
(0.97 to 1.07)		1.02
(0.97 to 1.07)		1.14
(0.97 to 1.32)		1.14
(0.97 to 1.32)
Nerve injury0.99
(0.96 to 1.02)		0.98
(0.96 to 1.01)		1.12
(1.00 to 1.24)		1.11
(0.99 to 1.24)		1.01
(0.95 to 1.07)		1.01
(0.95 to 1.07)		1.10
(0.98 to 1.24)		1.12
(0.99 to 1.26)
Other severe birth trauma0.96
(0.93 to 0.99)		0.96
(0.93 to 0.99)		1.04
(0.95 to 1.14)		1.05
(0.96 to 1.15)		0.95
(0.88 to 1.03)		0.95
(0.88 to 1.03)		1.00
(0.95 to 1.04)		1.00
(0.95 to 1.04)
Any severe birth trauma0.97
(0.95 to 0.98)		0.96
(0.95 to 0.98)		1.05
(0.99 to 1.11)		1.05
(0.99 to 1.11)		1.00
(0.97 to 1.04)		1.00
(0.97 to 1.04)		1.02
(0.98 to 1.06)		1.03
(0.99 to 1.07)

  • *Adjusted for parity, body mass index, maternal age, maternal education, race, marital status, assisted conception, hypertension, diabetes mellitus, gestational diabetes, smoking during pregnancy, birth weight, preterm birth, PROM (>12 hours), precipitous labour, prolonged labour, cephalopelvic disproportion, obstructed labour and fetal sex.

  • aOR, adjusted OR; PROM, premature rupture of membranes.