Table 1.
Demographic characteristics of adolescent boys from Chapaevsk, Russia (N = 30)
| Mean | SD | N | % | |
| Age (years) | 16.1 | 0.81 | ||
| Body Mass Index (kg/m2) | 19.9 | 3.09 | ||
| Weeks of Gestationa | 39.2 | 2.37 | ||
| Breastfeeding duration of index son (weeks)b | 36.9 | 25.2 | ||
| Prior maternal breastfeeding (weeks)b | 18.1 | 38.3 | ||
| Birth weight (gm)c | 3433 | 439 | ||
| Current residential distance to Khimprom factory (km) | 4.45 | 1.76 | ||
| Time boy resided in Chapaevsk(yrs) | 14.0 | 3.70 | ||
| Gravidityd | ||||
| 0 | 14 | 48 | ||
| 1 | 8 | 28 | ||
| 2–3 | 7 | 24 | ||
| Parityd | ||||
| 0 | 17 | 59 | ||
| 1 | 10 | 34 | ||
| 2–3 | 2 | 7 | ||
| Monthly family income level | ||||
| 300–1000 rubles ($10–$35 U.S.) | 8 | 28 | ||
| 1000–1500 rubles ($35–$50 U.S.) | 7 | 24 | ||
| >1500 rubles (> $50 U.S.) | 14 | 48 | ||
| Maximum parental education level | ||||
| 8–11thgrade | 2 | 7 | ||
| Junior College | 17 | 59 | ||
| University | 8 | 28 |
aOne subject was missing data on weeks of gestation of the index son.
bOne subject was missing data on breastfeeding. Prior maternal breastfeeding is the cumulative number of weeks of breastfeeding children born prior to the index son.
cTwo subjects were missing data on birth weight of the index son.
d Maternal gravidity is the number of pregnancies prior to the index son and parity is the number of live births prior to the index son.