Table 1.
Characteristics of mother-newborn pairs (n = 381)
| Characteristics | Mean ± SD or range and number (%) | |
|---|---|---|
| Maternal | ||
| Age, y | 29.0 | (18–42) |
| Pre-gestational BMI, kg/m2 | 24.3 | ± 4.5 |
| Maternal education | ||
| Low | 47 | (12.7%) |
| Middle | 132 | (34.7%) |
| High | 200 | (52.6%) |
| Smoking | ||
| Never-smoker | 255 | (66.9%) |
| Past-smoker | 65 | (17.1%) |
| Smoker | 61 | (16.0%) |
| Parity | ||
| 1 | 200 | (52.5%) |
| 2 | 141 | (37.0%) |
| ≥ 3 | 40 | (10.5%) |
| Mode of delivery | ||
| Caesarian section | 19 | (5.0%) |
| Newborn | ||
| Gender | ||
| Female | 193 | (50.7%) |
| Ethnicity | ||
| European | 332 | (87.1%) |
| Non-European | 49 | (12.9%) |
| Gestational age, w | 39.2 | (35–42) |
| Season at conception | ||
| Winter | 90 | (23.6%) |
| Spring | 87 | (22.8%) |
| Summer | 118 | (31.0%) |
| Fall | 86 | (22.6%) |
| Apgar score after 5 min | ||
| ≤ 8 | 22 | (5.7%) |
| 9 | 110 | (28.9%) |
| 10 | 249 | (65.4%) |
| Birth weight, g | 3431 | ± 425 |
| MT-RNR1 mtDNA methylation, %* | 9.54 | ± 4.2 |
| D-loop mtDNA methylation, %* | 3.60 | ± 1.28 (n = 356) |
| mtDNA content*,# | 1.04 | (0.45–2.45) |
*
Measured in placental tissue.
#
Geometric mean with 10th–90th percentiles.