Variable

NVD (n = 97)

C.S (n = 53)

t-test

P value

Cervical length (mm):

Mean ± SD

31.8 ± 2.7

34.2 ± 2.7

5.14

<0.001 (HS)

Uterocervical angle (˚):

Mean ± SD

116.3 ± 7.6

103.5 ± 10.8

8.42

<0.001 (HS)