Risk factors

Case n = 105

Control n = 210

Statistical Tests

n

%

n

%

COR (95% CI)

P

1) Maternal and reproductive health

Marriage age (year)

0.362

≤18

52

49.5

91

43.3

1.2 (0.8 - 2)

>19

53

50.5

119

56.7

1 (reference)

Age at the first menstruation (year)

0.150

<12

11

10.5

1

5.7

0.5 (0.2 - 1.3)

0.163

13 - 16

84

80.0

166

79.0

0.3 (0.1 - 1)

0.052

<16

10

9.5

32

15.3

1 (reference)

Age at the first pregnancy (year)

0.017

<18

25

29.4

39

20.6

1 (reference)

19 - 24

44

51.8

133

70.4

0.5 (0.3 - 0.9)

0.033

>24

16

18.8

17

9.0

1.3 (0.6 - 3)

0.545

Number of pregnancies

0.372

≤4

69

65.7

126

60.0

1.2 (0.8 - 2)

>5

36

34.3

84

40.0

1 (reference)

Number of deliveries

0.261

≤4

68

64.8

121

57.6

1.3 (0.8 - 2.1)

>5

37

35.2

89

42.4

1 (reference)

Number of abortions

0.257

≤2

78

74.3

170

81.0

1 (reference)

>3

27

25.7

40

19.0

1.4 (0.8 - 2.4)

The period between pregnancies (year)

0.206

≤1

19

23.5

50

31.8

1 (reference)

>2

62

76.5

107

68.2

1.5 (0.8 - 2.7)

Last pregnancy time (month)

0.002

<18

41

42.7

72

36.2

1 (reference)

19 - 24

36

37.5

113

56.8

0.6 (0.3 - 0.99)

0.034

>24

19

19.8

14

7.0

2.1 (1 - 4.6)

0.063

Use natural breastfeeding

0.198

Yes

77

87.5

177

92.2

0.6 (0.3 - 1.3)

No

11

12.5

15

7.8

1 (reference)

Difficulties in breastfeeding

0.562

Yes

15

17.0

25

13.0

1.2 (0.6 - 2.5)

No

73

83.0

167

87.0

1 (reference)