Table 4 Association between risk factors and birth defects
Risk factors | b | Chi-squre | P-value | RR | RR95%CI |
|---|---|---|---|---|---|
Ethnicity | |||||
Hana | — | — | — | 1.000 | — |
Mongolian | −0.172 | 41.05 | 0.000 | 0.842 | 0.799-0.888 |
Other | 0.008 | 0.01 | 0.905 | 1.008 | 0.888-1.138 |
Maternal age (years) | |||||
<25 | 0.798 | 374.28 | 0.000 | 2.220 | 2.048-2.408 |
25-- | 0.514 | 176.03 | 0.000 | 1.672 | 1.550-1.805 |
30-- | 0.227 | 20.34 | 0.000 | 1.255 | 1.137-1.385 |
35--a | — | — | — | 1.000 | — |
Smoking | |||||
Noa | — | — | — | 1.000 | — |
Yes | −0.129 | 2.12 | 0.145 | 0.879 | 0.736-1.041 |
Drinking | |||||
Noa | — | — | — | 1.000 | — |
Yes | 1.169 | 55.65 | 0.000 | 3.220 | 2.332-4.319 |
Time of pregnancy | |||||
1 | −1.769 | 1603.35 | 0.000 | 0.171 | 0.156-0.186 |
2 | −1.017 | 579.74 | 0.000 | 0.362 | 0.333-0.393 |
≧3a | — | — | — | 1.000 | — |
Parental consanguinity | |||||
Noa | — | — | — | 1.000 | — |
Yes | 0.305 | 3.73 | 0.053 | 1.356 | 0.981-1.822 |
Familial inheritance history | |||||
noa | — | — | — | 1.000 | — |
yes | 2.413 | 1480.85 | 0.000 | 11.165 | 9.852-12.600 |
Maternal education | |||||
Less than high school | 0.526 | 214.23 | 0.000 | 1.692 | 1.577-1.815 |
High school | 0.059 | 1.17 | 0.279 | 1.061 | 0.952-1.180 |
More than high schoola | — | — | — | 1.000 | — |
Living area | |||||
Urbana | — | — | — | 1.000 | — |
Rural | 0.576 | 393.87 | 0.000 | 1.779 | 1.681-1.884 |