Table 2 Comparison of pregnancy characteristics between study and reference groups

ART (%)

9.4 (12)

2.2 (5)

0.001^#

Gestation age at birth (weeks)

37.9 ± 1.6

39.3 ± 1.2

0.000^&

Gestation age at birth^a (weeks)

38.6 ± 0.9

39.4 ± 1.0

0.000^&

Cervical incompetence

1/112

0/224

/

PROM (%/n)

21.4 (24)

25.4 (57)

0.417^#

CAN (%/n)

54.5 (61)

29.9 (67)

0.000^#

CAN three times (%/n)

7.1 (8)

0.4 (1)

0.001^§

Manual placenta removal (%/n)

9.8 (11)

4.0 (9)

0.034^#

Postpartum hemorrhage (%/n)

2.7 (3)

4.5 (10)

0.617^§

Uterotonic usage (%/n)

40.2 (45)

37.5 (84)

0.634^#

Oligohydramnios (%/n)

3.6 (4)

0.9 (2)

0.098^§

Hypertensive disorders (%/n)

4.5 (5)

6.7 (15)

0.415^#

Gestational diabetes (%/n)

17.0 (19)

14.7 (33)

0.594^#

ICP (%/n)

2.7 (3)

1.3 (3)

0.404^*

Placenta previa (%/n)

2.7 (3)

0.4(1)

0.110^*

Placental abruption (%/n)

0.9 (1)

1.8 (4)

0.668^*