Table 1.
Characteristics of mother-newborn pairs according to self-reported tobacco smoke exposure during pregnancy
| Variable | All (n = 382) |
Non-smokers (n = 255) |
Past-smokers (n = 65) |
Smokers (n = 62) |
p value* |
|---|---|---|---|---|---|
| Newborn | |||||
| Sex | 0.47 | ||||
| Male | 188 (49.2%) | 120 (47.1%) | 34 (52.3%) | 34 (54.8%) | |
| Female | 194 (50.8%) | 135 (52.9%) | 31 (47.7%) | 28 (45.2%) | |
| Ethnicity | 0.73 | ||||
| European-Caucasian | 332 (86.9%) | 223 (87.4%) | 57 (87.7%) | 52 (83.9%) | |
| Non-European | 50 (13.1%) | 32 (12.6%) | 8 (12.3%) | 10 (16.1%) | |
| Gestational age, w | 39.2 ± 1.2 | 39.3 ± 1.2 | 39.2 ± 1.3 | 39.2 ± 1.2 | 0.82 |
| Birth weight, g | 3429 ± 426 | 3472 ± 424 | 3437 ± 423 | 3247 ± 395 | 0.0009 |
| Birth length, cm | 50.3 ± 1.9 | 50.5 ± 2.0 | 50.5 ± 1.7 | 49.5 ± 1.8 | 0.0007 |
| Mother | |||||
| Age, year | 29.0 ± 4.7 | 29.4 ± 4.5 | 28.9 ± 4.9 | 27.7 ± 4.8 | 0.03 |
| Pre-pregnancy BMI, kg/m2 | 24.3 ± 4.5 | 24.2 ± 4.4 | 24.8 ± 5.3 | 24.2 ± 4.1 | 0.65 |
| Maternal education | <0.0001 | ||||
| Low | 51 (13.3%) | 26 (10.2%) | 6 (9.2%) | 19 (30.6%) | |
| Middle | 131 (34.3%) | 77 (30.2%) | 25 (38.5%) | 29 (46.8%) | |
| High | 200 (52.4%) | 152 (59.6%) | 34 (52.3%) | 14 (22.6%) | |
| Medication usea | 0.57 | ||||
| None | 134 (37.8%) | 92 (39.5%) | 21 (32.3%) | 21 (37.5%) | |
| Alcohol consumption | 0.03 | ||||
| Occasionally | 73 (19.1%) | 42 (16.5%) | 20 (30.8%) | 11 (17.7%) | |
| Physical activity (>20 min)b | 0.40 | ||||
| <1 times per week | 122 (33.3%) | 82 (33.3%) | 19 (29.7%) | 21 (36.8%) | |
| 1 times per week | 86 (23.4%) | 63 (25.6%) | 15 (23.4%) | 8 (14.0%) | |
| >2 times per week | 159 (43.3%) | 101 (41.1%) | 30 (46.9%) | 28 (49.2%) | |
| Parity | 0.42 | ||||
| 1 | 200 (52.3%) | 132 (51.8%) | 36 (55.4%) | 32 (51.6%) | |
| 2 | 142 (37.2%) | 91 (35.7%) | 25 (38.5%) | 26 (41.9%) | |
| ≥3 | 40 (10.5%) | 32 (12.5%) | 4 (6.1%) | 4 (6.5%) | |
| Cigarettes before pregnancy | – | – | 11.0 ± 6.9 | 10.3 ± 6.7 | |
| Cigarettes during pregnancy | – | – | – | 7.8 ± 4.6 | |
Data are presented as arithmetic mean ± standard deviation (SD) or number (%)
* p value derived from one-way ANOVA or Chi square tests in case of continuous or categorical variables respectively
aMedication use: occasional use of paracetamol or antibiotics (28 missing data)
bMissing data for 15 subjects