Table 4.

Total duration of labor arrest (in hours) prior to intrapartum cesarean deliveries for “failure to progress/cephalopelvic disproportion” or “failed induction” among singleton, vertex presentation with and without a previous uterine scar

Cervical dilation at cesarean section (cm)	Nulliparas		Multiparas		Women with a previous uterine scar having a trial of labor Median (cumulative percentage)
	Spontaneous labor Median (cumulative percentage)	Induced labor Median (cumulative percentage)	Spontaneous labor Median (cumulative percentage)	Induced labor Median (cumulative percentage)
0	13.8 (0.3%)	14.5 (4%)	-- (0.1%)	16.0 (2%)	9.6 (2%)
1	10.0 (2%)	9.4 (10%)	-- (1%)	11.7 (6%)	6.3 (6%)
2	6.8 (3%)	5.6 (15%)	-- (3%)	8.6 (9%)	6.5 (16%)
3	4.0 (7%)	4.3 (23%)	6.9 (6%)	5.5 (16%)	5.0 (21%)
4	4.0 (17%)	4.0 (40%)	2.7 (14%)	3.4 (29%)	2.5 (36%)
5	3.5 (28%)	3.2 (53%)	4.0 (19%)	2.4 (44%)	2.8 (49%)
6	2.9 (38%)	2.8 (63%)	3.6 (31%)	2.5 (54%)	3.2 (62%)
7	2.8 (46%)	2.2 (69%)	2.8 (39%)	2.6 (63%)	2.4 (69%)
8	3.0 (56%)	2.6 (75%)	2.8 (53%)	2.9 (71%)	2.0 (75%)
9	2.2 (65%)	2.3 (81%)	2.8 (69%)	1.7 (83%)	1.3 (84%)
2nd stage	3.8 (100%)	3.5 (100%)	2.9 (100%)	2.8 (100%)	2.3 (100%)
Among the 2nd stage cesarean deliveries (cumulative percentage)
< 2 hr	12%	14%	24%	27%	39%
2 – 3 hr	33%	35%	55%	63%	56%
3 – 4 hr	55%	63%	74%	81%	76%
≥4 hr	100%	100%	100%	100%	100%

--: The number of subjects is too small to have a meaningful value.