Variable

Preterm birth

Total n (%)

p-value

Yes

No

N

(%)

n

(%)

Age

0.043

<20 year

86

42.8

115

57.2

201 (10.3)

20-35 year

469

34.4

894

65.6

1363 (70.1)

>35 year

125

32.9

255

67.1

380 (19.6)

Education

0.217

Elementary School

126

32.3

264

67.7

390 (20.1)

Middle School

228

37.7

377

62.3

605 (31.1)

High School

218

35.6

395

64.4

613 (31.5)

University

108

32.1

228

67.9

336 (17.3)

Antenatal care

<0.001

<4 times

68

52.3

62

47.7

130 (6.7)

≥4 times

612

33.7

1202

66.3

1,814 (93.3)

Parity

0.381

Primipara

299

35.6

542

64.4

841 (43.3)

Multipara

360

35.1

667

64.9

1,027 (52.8)

Grande Multipara

21

27.6

55

72.4

76 (3.9)

Pregnancy Interval

0.759

<24 months

54

37.5

90

62.5

144 (7.4)

≥24 months

362

35.1

669

64.9

1031 (53)

First pregnancy

264

34.3

505

65.7

769 (39.6)

Labor Histories Preterm birth history

<0.001

Yes

74

54.8

61

45.2

135 (6.9)

No

606

33.5

1203

66.5

1809 (93.1)

History of abortion

0.422

Yes

101

37.1

171

62.9

272 (14)

No

579

34.6

1093

65.4

1672 (86)

Anemia

<0.001

Yes

195

42.1

268

57.9

463 (23.8)

No

485

32.7

996

67.3

1481 (76.2)

Hypertension

<0.001

No hypertension

483

33.5

959

66.5

1442 (74.2)

Gestational hypertension

16

17.4

76

82.6

92 (4.7)

Preeclampsia

137

46

161

54

298 (15.3)

Eclampsia

30

66.7

15

33.3

45 (2.3)

Chronic hypertension

14

20.9

53

79.1

67 (3.4)

Antepartum hemorrhage

<0.001

Yes

76

75.2

25

24.8

101 (5.2%)

No

604

24.8

1239

67.2

1843 (94.8)

PROM

0.649

Yes

107

33.9

209

66.1

316 (16.3)

No

573

35.2

1055

64.8

1628 (83.7)

Total

1264

65

680

35

1944