Definition of ROM

Rate of CC with early ROM

Rate of CC with late ROM

p-Value

Modified Bishop score

All women (N = 279)

Nulliparous (N = 133)

Multiparous (N = 146)

<5

14% (7/50)

25% (5/20)

6.7% (2/30)

≥5

7.4% (17/229)

11.5% (13/113)

3.5% (4/116)

0.161

0.148

0.603

Cervical dilation

All women (N = 279)

Nulliparous (N = 133)

Multiparous (N = 146)

<4 cm

5.4% (2/37)

4.7% (1/21)

6.3% (1/16)

≥4 cm

9.1% (22/242)

15.2% (17/112)

3.9% (5/130)

0.752

0.304

0.508

Cervical effacement

All women (N = 279)

Nulliparous (N = 133)

Multiparous (N = 146)

<80%

15.4% (12/78)

27.6% (8/29)

8.2% (4/49)

≥80%

6% (12/201)

9.6% (10/104)

2% (2/98)

0.017

0.027

0.095