Characteristics

Spontaneous preterm delivery < 37 weeks (n = 8)

Term delivery ≥ 37 weeks (n = 119)

p-value

Maternal age, years

32.0 ± 5.3

30.8 ± 6.2

0.58

Height, cm

161.5 ± 8.4

162.7 ± 6.7

0.96

Weight, kg

82.7 ± 13.8

81.1 ± 17.9

0.80

Parous women

4 (50%)

45 (38%)

-

Prior history of PTB

2 (25%)

11 (9%)

-

Gestational age at CM examination, weeks + days

27 + 1

26 + 4

0.32

Gestational age at birth, weeks + days

34 + 5

39 + 1

4.7 × 10⁻²²

Anterior cervical length, mm

34.9 ± 9.8

30.8 ± 8.5

0.19

Posterior cervical length, mm

34.8 ± 8.8

30.1 ± 7.2

0.08

Average anterior and posterior cervical length, mm

34.9 ± 7.7

30.4 ± 6.8

0.11

Anterior cervical elasticity (stress-to-strain ration), kPa/mm

0.73 ± 0.44

1.67 ± 0.89

3.6 × 10⁻³

Posterior cervical elasticity (stress-to-strain ration), kPa/mm

0.68 ± 0.21

1.58 ± 0.59

3.0 × 10⁻⁵

Average anterior and posterior cervical elasticity (stress-to-strain ration), kPa/mm

0.70 ± 0.26

1.63 ± 0.65

1.1 × 10⁻⁴