Variable

Mean ± SD

Range

Maternal age (years)

30.42 ± 4.85

20 - 43

History of live births

0.1 ± 0.3

0 - 1

Number of previous miscarriages

2. 37 ± 1.35

0 - 7

Gestation at cerclage (weeks)

16.2 ± 3.23

12.00 - 26.57

Cervical length (cm)

2.83 ± 0.90

0.00 - 4.60

Cervical dilatation (cm)

1.54 ± 0.71

0.4 - 2.5