Table 3 Basic characteristics of the Sapporo cohort participants (n = 514)
From: The Hokkaido Birth Cohort Study on Environment and Children’s Health: cohort profile—updated 2017
Number | Mean (±SD), Med (25–75%), or % | |
|---|---|---|
Maternal characteristics | ||
Age at entry (years) | 510 | 30.4 ± 4.9 |
Maternal body mass index | 506 | 21.2 ± 3.2 |
Nulliparous (%) | 240 | 47.7 |
Education (years) | ||
≤9 | 14 | 2.8 |
10–12 | 211 | 41.5 |
13–16 | 274 | 53.9 |
≥17 | 9 | 1.8 |
Household income (million yen/year) | ||
<3 | 95 | 18.8 |
3 to <5 | 250 | 49.5 |
5 to <7 | 105 | 20.8 |
7 to 10 | 48 | 9.5 |
≥10 | 7 | 1.4 |
Drinking habit during pregnancy (%) | 157 | 30.9 |
Smoking habit during pregnancy (%) | 103 | 20.3 |
Caffeine intake during pregnancy (mg/day) | 508 | 124 (76–188) |
Paternal characteristics | ||
Age at entry (years) | 503 | 32.3 ± 5.6 |
Education (years) | ||
≤9 | 31 | 6.1 |
10–12 | 190 | 37.5 |
13–16 | 242 | 47.8 |
≥17 | 43 | 8.5 |
Smoking habit during pregnancy (%) | 354 | 69.8 |
Child characteristics | ||
Sex, boys (%) | 246 | 48.1 |
Gestational age (weeks) | 504 | 38.9 ± 1.5 |
Birth weight (g) | 511 | 3025.6 ± 420.7 |
Birth length (cm) | 511 | 47.9 ± 2.2 |
Types of delivery, vaginal (%) | 397 | 78.8 |