Table 1 Characteristics of mother-newborn pairs ( n = 240)
From: Placental DNA hypomethylation in association with particulate air pollution in early life
| Characteristics | Mean ± SD or range and number (%) |
|---|---|
| Maternal | |
| Age, y | 29.1 (18–42) |
| Pre-gestational BMI, kg/m2 | 24.4 ± 4.5 |
| Net weight gain, kg | 14.6 ± 6.4 |
| Maternal education | |
| Low | 30 (12.5%) |
| Middle | 84 (35.0%) |
| High | 126 (52.5%) |
| Smoking | |
| Never-smoker | 162 (67.6%) |
| Past-smoker | 39 (16.2%) |
| Smoker | 39 (16.2%) |
| Acetaminophen | |
| No | 136 (56.7%) |
| Yes | 104 (43.3%) |
| Alcohola | |
| No | 194 (82.5%) |
| Yes | 41 (17.5%) |
| Parity | |
| 1 | 128 (53.3%) |
| 2 | 88 (36.7%) |
| ≥ 3 | 24 (10.0%) |
| Apparent temperature, °C | |
| Trimester 1 | 9.4 ± 6.0 |
| Trimester 2 | 8.3 ± 6.2 |
| Trimester 3 | 8.6 ± 5.9 |
| Newborn | |
| Newborn’s gender | |
| Male | 110 (45.8%) |
| Female | 130 (54.2%) |
| Ethnicityb | |
| European | 206 (86.5%) |
| Non-European | 32 (13.5%) |
| Gestational age, w | 39.2 (35–42) |
| Seasonc | |
| Fall | 56 (23.3%) |
| Winter | 60 (25.0%) |
| Spring | 51 (21.3%) |
| Summer | 73 (30.4%) |
| Apgar score after 5 min | |
| 7 | 2 (0.8%) |
| 8 | 11 (4.6%) |
| 9 | 74 (30.8%) |
| 10 | 153 (63.8%) |
| Birth weight, g | 3400.8 ± 422.3 |
| Birth length, cm | 50.2 ± 1.9 |
| Placental global DNA methylation, % | 4.6 ± 0.4 |