Table 1 Characteristics and distribution for risk factors between CHD and no CHD groupa
From: Incidence and risk factors of congenital heart disease in Qingdao: a prospective cohort study
Risk factors | Total | CHD n (%) | No CHD n (%) | χ2 value | P value |
|---|---|---|---|---|---|
Twin pregnancy | |||||
No | 63,590 | 582 (0.92%) | 63,008(99.08%) | 7.801 | 0.005 |
Yes | 1173 | 20(1.71%) | 1153(98.29%) | ||
Maternal age (years) | |||||
< 35 | 51,651 | 484(0.94%) | 51,167(99.06%) | 1.560 | 0.692 |
≥ 35 | 13,112 | 118(0.90%) | 12,994(99.10%) | ||
BMI (kg/m2) | |||||
< 18.5 | 5269 | 61(1.16%) | 5208(98.84%) | −1.162 | 0.245 |
18.5–24.9 | 37,202 | 361(0.97%) | 36,841(99.03%) | ||
≥ 25 | 11,603 | 108(0.93%) | 11,495(99.07%) | ||
Living location | |||||
City | 40,274 | 424(1.05%) | 39,850(98.95%) | 8.334 | 0.004 |
Countryside | 15,324 | 120(0.78%) | 15,204(99.22%) | ||
Assisted reproduction | |||||
No | 54,827 | 531(0.97%) | 54,296(99.03%) | 3.704 | 0.054 |
Yes | 789 | 13(1.65%) | 776(97.25%) | ||
Maternal educational level | |||||
Low | 11,957 | 92(0.77%) | 11,865(99.23%) | −3.274 | 0.001 |
Medium | 40,605 | 409(1.01%) | 40,196(98.99%) | ||
High | 3043 | 43(1.41%) | 3000(98.59%) | ||
Dietary patterns | |||||
Well-balanced diet | 47,409 | 465(0.98%) | 46,944(99.02%) | −0.114 | 0.909 |
Eat less meat | 6440 | 61(0.95%) | 6379(99.05%) | ||
Eat less vegetables | 1747 | 18(1.03%) | 1729(98.07%) | ||
Husband age (years) | |||||
< 35 | 38,489 | 395(1.03%) | 38,095(98.97%) | 2.892 | 0.089 |
≥ 35 | 17,081 | 149(0.87%) | 16,932(99.13%) | ||
Number of previous pregnancies | |||||
0 | 17,500 | 189(1.08%) | 17,311(98.92%) | −2.215 | 0.027 |
1 | 20,106 | 201(1.00%) | 19,905(99.00%) | ||
> 1 | 18,013 | 153(0.85%) | 17,860(99.15%) | ||
Fertility history | |||||
0 | 26,021 | 288(1.11%) | 25,733(98.89%) | 8.615 | 0.003 |
≥ 1 | 29,598 | 255(0.86%) | 29,343(99.14%) | ||
History of having a child with birth defects | |||||
No | 55,015 | 531(0.97%) | 54,484(99.03%) | 6.449 | 0.011 |
Yes | 604 | 12(1.99%) | 592(98.01%) | ||
History of illness in the first trimester | |||||
No | 47,776 | 446(0.93%) | 47,330(99.07%) | 6.940 | 0.008 |
Yes | 7844 | 98(1.25%) | 7746(98.75%) | ||
Family history of birth defect | |||||
No | 55,222 | 534(0.97%) | 54,688(99.03%) | 9.746 | 0.002 |
Yes | 398 | 10(2.51%) | 388(97.49%) | ||
Family history of CHD | |||||
No | 55,521 | 537(0.97%) | 54,984(99.03%) | 38.012 | < 0.001 |
Yes | 99 | 7(7.07%) | 92(92.93%) | ||
History of folic acid intake | |||||
Does not eat folic acid | 3423 | 21(0.61%) | 3402(99.39%) | −2.279 | 0.022 |
Eating folic acid 3 months before after pregnancy | 37,683 | 364(0.97%) | 37,319(99.03%) | ||
Eating folic acid 6 months before and after Pregnancy | 14,514 | 159(1.10%) | 14,355(98.90%) | ||
History of husband smoking (cigarettes) | |||||
0 | 34,101 | 355(1.04%) | 33,746(98.96%) | −1.641 | 0.101 |
< 10 | 10,674 | 87(0.82%) | 10,587(99.18%) | ||
10–19 | 7059 | 68(0.96%) | 6991(99.04%) | ||
≥ 20 | 3786 | 34(0.90%) | 3752(99.10%) | ||