Table 6.

Multivariable analysis of duration of operative vaginal delivery for adverse outcomes

		Failed operative vaginal delivery	Severe perineal laceration	Composite adverse neonatal outcomes
Vacuum (n = 3,594)	Number of pop-offs
	0	Referent	Referent	Referent
	1	2.08 (1.31, 3.30)	0.95 (0.72, 1.25)	1.49 (0.88, 2.52)
	2	3.57 (2.21, 5.77)	1.10 (0.79, 1.52)	1.89 (1.03, 3.45)
	3+	11.27 (6.82, 18.63)	1.61 (1.06, 2.43)	2.00 (0.90, 4.45)
	Duration (min)
	0–2	Referent	Referent	Referent
	3–5	1.15 (0.59, 2.22)	1.21 (0.89, 1.65)	2.36 (1.04, 5.36)
	6–8	2.43 (1.26, 4.68)	1.06 (0.73, 1.54)	2.70 (1.10, 6.64)
	9–11	2.83 (1.33, 6.06)	1.08 (0.66, 1.77)	3.17 (1.08, 9.32)
	12+	6.52 (3.59, 11.85)	1.03 (0.70, 1.53)	3.70 (1.50, 9.13)
Forceps (n = 1,731)	Number of pulls
	1	Referent	Referent	Referent
	2	2.45 (1.22, 4.90)	1.70 (1.24, 2.33)	0.62 (0.27, 1.43)
	3+	3.07 (1.49, 6.33)	1.36 (0.94, 1.97)	1.15 (0.52, 2.55)
	Duration (min)
	0–2	Referent	Referent	Referent
	3–5	1.14 (0.44, 2.96)	1.10 (0.76, 1.58)	1.63 (0.51, 5.25)
	6–8	2.49 (0.93, 6.66)	0.95 (0.61, 1.49)	1.79 (0.47, 6.75)
	9–11	2.90 (0.91, 9.29)	1.09 (0.59, 2.02)	2.46 (0.51, 11.88)
	12+	2.57 (0.84, 7.85)	1.41 (0.81, 2.44)	4.98 (1.38, 17.98)

Note: Data are reported as aOR (95% CI) after adjusting for indication for operative vaginal delivery, fetal station, and position, maternal age and race/ethnicity, chorioamnionitis, prior vaginal deliveries, prior cesareans, and maternal BMI. Emboldened text represents statistical significance.