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) | |||||