. Author manuscript; available in PMC: 2012 Sep 1.

Published in final edited form as: Am J Obstet Gynecol. 2011 Jun 23;205(3):244.e1–244.e8. doi: 10.1016/j.ajog.2011.06.014

Table 4.

Adjusted^a Duration of Labor (hours) in Multiparas by Body Mass Index Category

	Body Mass Index Categories (kg/m²) at Admission with Median Traverse Times (95^th%)					P-value for Trend
Cervical Dilation (cm)	<25.0	25.0–29.9	30.0–34.9	35.0–39.9	≥40.0
4–5	1.2 (5.4)	1.2 (5.3)	1.2 (5.6)	1.2 (5.7)	1.5 (6.8)	<0.0001
5–6	0.7 (2.7)	0.7 (2.7)	0.7 (2.7)	0.7 (2.9)	0.7 (2.9)	<0.0001
6–7	0.5 (1.6)	0.5 (1.6)	0.5 (1.6)	0.5 (1.7)	0.5 (1.8)	<0.0001
7–8	0.4 (1.1)	0.4 (1.1)	0.4 (1.1)	0.4 (1.1)	0.4 (1.1)	0.67
8–9	0.3 (0.9)	0.3 (0.9)	0.3 (0.9)	0.3 (0.9)	0.3 (0.9)	0.92
9–10	0.3 (0.8)	0.3 (0.8)	0.3 (0.8)	0.3 (0.9)	0.3 (0.9)	0.02
4–10	4.6 (17.5)	4.5 (17.4)	4.7 (17.9)	5.0 (19.0)	5.4 (20.6)	<0.0001
2^nd stage without epidural	0.17 (1.0)	0.17 (1.0)	0.15 (0.9)	0.15 (0.9)	0.12 (0.7)	<0.0001
2^nd stage with epidural	0.40 (1.7)	0.33 (1.5)	0.27 (1.2)	0.25 (1.1)	0.36 (1.6)	<0.0001

Adjusted model controlled for age, height, race, gestational age, diabetes, induction, augmentation, epidural [first stage only], operative vaginal delivery [second stage only], and birth weight.