Covariates |
Preterm(n=285) |
Preterm(n=285) |
Full-term(n=6216) |
Full-term(n=6216) |
PTB rates(%) |
Χ2
|
P-value |
|
n |
% |
n |
% |
|
|
|
Mother |
|
|
|
|
|
|
|
Age (years) |
|
|
|
|
|
11.229 |
0.004 |
<25 |
17 |
5.96 |
520 |
8.37 |
3.17 |
|
|
25-30 |
106 |
37.19 |
2785 |
44.80 |
3.67 |
|
|
>30 |
162 |
56.84 |
2911 |
46.83 |
5.27 |
|
|
Occupation |
|
|
|
|
|
5.200 |
0.023 |
Other |
210 |
73.68 |
4940 |
79.47 |
4.08 |
|
|
Housewife |
75 |
26.32 |
1276 |
20.53 |
5.55 |
|
|
Education (years) |
|
|
|
|
|
3.719 |
0.156 |
≤9 |
27 |
9.47 |
568 |
9.14 |
4.54 |
|
|
10-12 |
61 |
21.40 |
1064 |
17.12 |
5.42 |
|
|
>12 |
197 |
69.12 |
4584 |
73.75 |
4.12 |
|
|
Pregnancy |
|
|
|
|
|
|
|
Parity |
|
|
|
|
|
4.554 |
0.033 |
Primiparous |
122 |
42.81 |
3074 |
49.45 |
3.82 |
|
|
Multiparous |
163 |
57.19 |
3142 |
50.55 |
4.93 |
|
|
Delivery mode |
|
|
|
|
|
24.499 |
<0.001 |
natural birth |
114 |
40.00 |
3426 |
55.12 |
3.22 |
|
|
cesarean |
171 |
60.00 |
2790 |
44.88 |
5.78 |
|
|
Complications |
|
|
|
|
|
80.40 |
<0.001 |
Yes |
46 |
16.14 |
268 |
4.31 |
14.65 |
|
|
No |
239 |
83.86 |
5948 |
95.69 |
3.86 |
|
|
Work |
|
|
|
|
|
<0.001 |
0.997 |
Yes |
175 |
61.40 |
3829 |
61.60 |
4.45 |
|
|
No |
110 |
38.60 |
2387 |
38.40 |
4.41 |
|
|
Tobacco exposure |
|
|
|
|
|
0.0688 |
0.793 |
Yes |
41 |
14.39 |
941 |
15.14 |
4.18 |
|
|
No |
244 |
85.61 |
5275 |
84.86 |
4.42 |
|
|
Infant |
|
|
|
|
|
|
|
Gender |
|
|
|
|
|
1.639 |
0.200 |
Male |
164 |
57.54 |
3209 |
51.62 |
4.86 |
|
|
Female |
121 |
42.46 |
3007 |
48.38 |
3.87 |
|
|
Family |
|
|
|
|
|
|
|
Income(yuan/month) |
|
|
|
|
|
5.415 |
0.020 |
<6000 |
49 |
17.19 |
767 |
12.34 |
6.00 |
|
|
≥6000 |
236 |
82.81 |
5449 |
87.66 |
4.15 |
|
|