Table 1 Comparisons of characteristics between shivering and non-shivering groups

Age, years, M ± SD

35.7 ± 4.6

37.6 ± 4.1

BMI, kg/m², M ± SD

27.1 ± 3.4

27.1 ± 2.6

Gestational age, week, M ± SD

38.8 ± 1.8

38.7 ± 1.5

Enter OR time, N (%)

 0–8 o’clock,

8 (9%),

5 (4.1%),

 8–12 o’clock,

37 (41.6%),

66 (53.7%),

 12–18 o’clock,

33 (37.1%),

49 (39.8%),

 18–24 o’clock

11 (12.4%)

3 (2.4%)

Anxiety, median (IQR)

1 (1, 1)

1 (1, 1)

Visual analog scale, N (%)

 0–3

66 (74.2)

115 (93.5)

 4–6

10 (11.2)

8 (6.5)

 7–10

13 (14.6)

0 (0)

Type of delivery, N (%)

 Elective

28 (31.5)

87 (70.7)

 Emergency

61 (68.5)

36 (29.3)

Transfer origin, N (%)

 From delivery room

35 (39.3)

9 (7.3)

 From ward

54 (60.7)

114 (92.7)

Labor analgesia, N (%)

28 (31.5)

7 (5.7))

Time from labor analgesia, hour, median (IQR)

0 (0, 4.25)

0 (0, 0)

Membrane rupture, N (%)

42 (47.2)

62 (16.3)

Time from membrane rupture, hour, median (IQR)

0 (0, 7)

0 (0, 0)

Dilation of cervix, centimeter, median (IQR)

0 (0, 2.75)

0 (0, 0)

Labor stage, N (%)

 Not in labor

49 (55.1)

102 (82.9)

 Latent period

23 (25.8)

18 (14.6)

 Active period

13 (14.6)

2 (1.6)

 Second stage of labor

4 (4.5)

1 (0.8)

Time of labor entry, hour, M ± SD

5.0 ± 8.8

1.2 ± 3.7

Operation indications, N (%)

 Scarred uterus,

34 (38.6)

80 (65)

 Fetal distress,

15 (17)

7 (5.7)

 Labor stagnation

4 (4.5)

1 (0.8)

 Twins

4 (4.5)

11 (8.9)

 Malposition,

7 (8)

5 (4.1)

 Intrauterine infection

12 (13.6)

4 (3.3)

 PIH

2 (2.3)

2 (1.6)

 Others

10 (11.4)

13 (10.6)

Sensory block level, M ± SD

5.1 ± 0.8

5.0 ± 0.8

Operation duration, minute, M ± SD

47.7 ± 14.8

47.6 ± 12.7

Blood loss, milliliter, M ± SD

223.6 ± 79.8

210.6 ± 42.1