Table 2 Unadjusted and adjusted associations between smoking during pregnancy and potential predictors.
Sample size | Smoking during pregnancy | Unadjusted odds ratio | Adjusted odds ratio | |
|---|---|---|---|---|
N* | N*(%) | OR (95% CI)† | OR (95% CI) † | |
Household income | ||||
< $30,000 | 1,031 | 230 (22.3) | 10.12 (6.77-15.13) | 1.73 (1.08-2.78) |
$30,000 to less than $60,000 | 1,853 | 242 (13.1) | 5.31 (3.54-7.95) | 1.86 (1.21-2.85) |
$60,000 to less than $100,000 | 1,940 | 111 (5.7) | 2.14 (1.39-3.30) | 1.09 (0.71-1.69) |
≥ $100,000 | 1,212 | 33 (2.7) | 1 | 1 |
Place of residence | ||||
Rural area | 1,100 | 150 (13.6) | 2.23 (1.78-2.80) | 1.40 (1.04-1.87) |
Urban, population ≤ 499,999 | 2,283 | 310 (13.6) | 2.22 (1.81-2.72) | 1.42 (1.10-1.82) |
Urban, population ≥ 500,000 | 2,791 | 185 (6.6) | 1 | 1 |
Immigrant | ||||
No | 4,980 | 641 (12.9) | 7.26 (4.79-11.00) | 5.32 (3.32-8.51) |
Yes | 1,407 | 28 (2.0) | 1 | 1 |
Work during pregnancy | ||||
No | 1,364 | 195 (14.3) | 1.60 (1.34-1.91) | 0.93 (0.72-1.20) |
Yes | 5,028 | 475 (9.4) | 1 | 1 |
Marital status | ||||
No partner | 535 | 168 (31.4) | 4.88 (3.97-6.01) | 1.83 (1.33-2.53) |
Have a partner | 5,860 | 501 (8.5) | 1 | 1 |
Moms perceived health | ||||
Excellent/very good | 4,645 | 396 (8.5) | 1 | 1 |
Good | 1,419 | 208 (14.7) | 1.84 (1.53-2.21) | 1.17 (0.92-1.49) |
Poor/Fair | 341 | 69 (20.2) | 2.70 (2.03-3.60) | 1.01 (0.67-1.51) |
Alcohol drinking during pregnancy | ||||
No | 5,713 | 576 (10.1) | 1 | 1 |
Yes | 669 | 89 (13.3) | 1.36 (1.06-1.74) | 1.28 (0.93-1.77) |
Health problems during pregnancy | ||||
No | 4,837 | 485 (10.0) | 1 | 1 |
Yes | 1,563 | 186 (11.9) | 1.21 (1.01-1.46) | 1.19 (0.95-1.50) |
Reaction when discovered pregnancy | ||||
Very happy/happy | 5,940 | 576 (9.7) | 1 | 1 |
Indifferent | 265 | 58 (21.9) | 2.63 (1.94-3.56) | 1.09 (0.71-1.69) |
Very unhappy/Unhappy | 180 | 36 (20.0) | 2.35 (1.60-3.46) | 0.93 (0.54-1.61) |
Attended prenatal classes | ||||
No | 4,306 | 528 (12.3) | 1.89 (1.56-2.28) | 1.43 (1.10-1.86) |
Yes | 2,097 | 144 (6.9) | 1 | 1 |
Support during pregnancy | ||||
None/Little of time | 328 | 50 (15.2) | 1.59 (1.15-2.21) | 1.25 (0.82-1.91) |
Some of the time | 502 | 52 (10.4) | 1.03 (0.76-1.39) | 0.97 (0.65-1.46) |
Most/All of time | 5,555 | 567 (10.2) | 1 | 1 |
Passive smoking during pregnancy | ||||
No | 4,903 | 206 (4.2) | 1 | 1 |
Yes | 1,499 | 466 (31.1) | 10.28 (8.64-12.23) | 5.31 (4.28-6.58) |
Province‡ | ||||
Eastern-Atlantic | 379 | 51 (13.5) | 1 | 1 |
Eastern-Central | 4,018 | 385 (9.6) | 0.69 (0.57-0.83) | 1.27 (0.85-1.89) |
Western-Prairies | 1,220 | 159 (13.0) | 0.97 (0.78-1.21) | 1.15 (0.74-1.76) |
Western-British Columbia | 755 | 64 (8.5) | 0.60 (0.44-0.82) | 1.24 (0.76-2.02) |
Northern territories | 33 | 13 (39.4) | 4.09 (3.32-5.05) | 2.29 (0.73-7.14) |
Unadjusted Mean difference § (95% CI)† | ||||
Years of education | 6,349 | -2.57 (-2.77--2.36) | 0.84 (0.80-0.88) | |
Age at first pregnancy | 6,332 | -4.89 (-5.31--4.47) | 0.93 (0.90-0.96) | |
Number of past pregnancies | 6,397 | 0.62 (0.46-0.77) | 1.08 (0.99-1.18) | |
Mother's age at selected birth | 6,368 | -2.88 (-3.36--2.39) | 1.04 (1.01-1.07) | |
Weight gained during pregnancy | 6,332 | 0.50 (-0.20-1.21) | -- | |
Number of stressful events | 6,353 | 1.25 (1.07-1.42) | 1.15 (1.08-1.23) | |
Number of prenatal visits | 6,138 | 0.20 (-0.23-0.64) | -- | |