Table 2 Maternal, Fetal Antenatal and Intrapartum Characteristics of Women with Shoulder Dystocia (N = 198)

 Ethnicity

Chinese

140 (95.2)

48 (94.1)

Other Asian

7 (4.8)

3 (5.9)

0.753

 Maternal Age

Mean ± SD

31 ± 4.8

30 ± 5.2

0.300

<35 years

113 (76.9)

40 (78.4)

≥35 years

34 (23.1)

11 (21.6)

0.819

 Maternal Height (cm)^a

Mean ± SD

156 ± 6.0

156 ± 5.5

0.737

>150

120 (81.6)

45 (88.2)

≤150

24 (16.3)

4 (7.8)

0.144

 Maternal Weight at delivery (kg)

68.1 ± 9.9

71.7 ± 9.2

0.034

 Maternal BMI at booking (kg/m²)^b

Mean ± SD

24.1 ± 3.9

24.8 ± 3.5

0.312

<30

128 (87.1)

45 (88.2)

≥30

14 (9.5)

2 (3.9)

0.232

 Maternal BMI at delivery (kg/m²)^c

Mean ± SD

27.8 ± 3.4

29.2 ± 3.5

0.015

<30

108 (72.5)

29 (56.9)

≥30

31 (21.1)

17 (33.3)

0.049

 Parity

Nulliparous

76 (51.7)

20 (39.2)

Multiparous

71 (48.3)

31 (60.8)

0.124

 Pre-existing/Gestational Diabetes Mellitus

No

134 (91.1)

45 (88.2)

Yes

13 (8.8)

6 (11.8)

0.542

 Onset of Labour

Spontaneous

112 (76.2)

43 (84.3)

Induced

35 (23.8)

8 (15.7)

0.285

 Duration of 2^nd stage (minutes)^d

Mean ± SD

55 ± 41.2

42 ± 40.7

0.056

Normal (≤60 min)

84 (57.1)

37 (72.5)

Prolonged (>60 min)

61 (41.5)

13 (25.5)

0.043

 Mode of Delivery

Spontaneous vaginal

34 (23.1)

31 (60.8)

Instrumental

113 (76.9)

20 (39.2)

<0.001

 Epidural

With

25 (17.0)

6 (11.8)

Without

122 (83.0)

45 (88.2)

0.375

 Gestation (weeks)

39 ± 1.2

39 ± 1.2

0.658

 Sex

Male

91 (61.9)

28 (54.9)

Female

56 (38.1)

23 (45.1)

0.379

 Body Weight (kg)

Mean ± SD

3.78 ± 0.39

3.87 ± 0.38

0.178

<4 kg

102 (69.4)

33 (64.7)

≥4 kg

45 (30.6)

18 (35.3)

0.536