Table 2.

Association between findings at 39 weeks gestation and labor onset within 1 week; analysis by the Cox proportional hazard model.

	Univariate			Multivariate
	HR	95% CI	p value	HR	95% CI	p value
Age	1.00	1.00–1.02	0.75	1.00	0.97–1.03	0.86
Height	1.02	0.99–1.05	0.26	0.98	0.83–1.16	0.83
Body weight	1.00	099–1.02	0.50	1.04	0.86–1.26	0.68
Body mass index	1.01	0.98–1.04	0.61	0.91	0.55–1.51	0.72
Obstetric history (primipara vs. multipara)	1.58	1.11–2.26	0.01	1.11	0.77–1.61	0.58
Bishop score (0–2 vs. 3–5 vs. 6–8)	2.92	1.40–3.43	< 0.0001	1.81	1.40–2.34	< 0.0001
Elastography (hard tissue vs. medium hard tissue vs. soft tissue)	2.04	1.64–2.54	< 0.0001	1.86	1.46–2.35	< 0.0001

HR hazard ratio, CI confidence interval.