Table 3.
Baseline and outcome characteristics by quartile group of total PCB exposure.
| Quartile groups of total PCB exposure
|
||||
|---|---|---|---|---|
| Quartile group [μg/L (mean PCB level)] | 1 (5.8) | 2 (7.7) | 3 (9.4) | 4 (13.8) |
| Total sample (n = 150) | ||||
| Birth weight (g) | 3,202 ± 578 | 3,010 ± 551 | 3,033 ± 477 | 3,129 ± 615 |
| Birth length (cm) | 50.0 ± 2.5 | 49.3 ± 3.4 | 49.1 ± 2.5 | 49.6 ± 2.9 |
| Gestational age at delivery (weeks) | 39.2 ± 2.6 | 38.6 ± 3.6 | 37.9 ± 4.0 | 38.5 ± 3.2 |
| Parity | 1.7 ± 1.2 | 1.9 ± 1.3 | 2.6 ± 2.0 | 1.8 ± 1.1 |
| Maternal age (years) | 23.9 ± 6.1 | 25.6 ± 6.1 | 26.5 ± 6.2 | 27.6 ± 6.1 |
| Maternal prepregnancy weight (lbs) | 138 ± 30 | 132 ± 26 | 139 ± 26 | 128 ± 17 |
| Maternal height (in) | 64 ± 3 | 65 ± 3 | 65 ± 2 | 64 ± 2 |
| Maternal smoking during pregnancy (%) | 41 | 43 | 41 | 42 |
| Maternal years of education | 11.4 ± 1.4 | 11.6 ± 1.9 | 10.9 ± 2.5 | 11.3 ± 2.1 |
| Family income at registration ($) | 4,019 ± 1,673 | 4,379 ± 2,261 | 5,067 ± 2,373 | 5,719 ± 2,624 |
| Socioeconomic index at registration | 59.8 ± 19.2 | 51.3 ± 21.6 | 54.3 ± 18.3 | 55.5 ± 15.4 |
| Girls (n = 41) | ||||
| Birth weight (g) | 3,050 ± 786 | 3,064 ± 470 | 3,070 ± 403 | 3,082 ± 499 |
| Birth length (cm) | 49.3 ± 3.2 | 49.0 ± 2.0 | 49.0 ± 2.7 | 49.3 ± 2.2 |
| Gestational age at delivery (weeks) | 38.5 ± 3.2 | 38.7 ± 2.8 | 39.3 ± 1.5 | 39.0 ± 0.9 |
| Parity | 2.0 ± 1.0 | 2.0 ± 1.8 | 3.4 ± 3.0 | 2.1 ± 0.9 |
| Maternal age (years) | 27.3 ± 7.0 | 25.8 ± 7.5 | 29.9 ± 6.1 | 29.3 ± 5.6 |
| Maternal prepregnancy weight (lbs) | 139 ± 23 | 135 ± 22 | 150 ± 30 | 132 ± 10 |
| Maternal height (in) | 64 ± 2 | 66 ± 2 | 65 ± 2 | 64 ± 2 |
| Maternal smoking during pregnancy (%) | 30 | 36 | 71 | 30 |
| Maternal years of education | 12.3 ± 1.4 | 11.4 ± 2.4 | 10.9 ± 1.7 | 11.0 ± 2.5 |
| Family income at registration ($) | 4,333 ± 1,472 | 4,722 ± 2,539 | 5,278 ± 1,394 | 5,398 ± 2,619 |
| Socioeconomic index at registration | 48.4 ± 16.7 | 48.9 ± 25.0 | 55.6 ± 20.1 | 54.1 ± 19.6 |
| Boys (n = 109) | ||||
| Birth weight (g) | 3,256 ± 440 | 3,035 ± 623 | 2,898 ± 589 | 3,195 ± 579 |
| Birth length (cm) | 50.2 ± 2.0 | 49.9 ± 4.0 | 48.6 ± 3.2 | 50.0 ± 2.6 |
| Gestational age at delivery (weeks) | 39.3 ± 2.0 | 39.0 ± 4.4 | 36.7 ± 4.7 | 38.6 ± 3.0 |
| Parity | 1.5 ± 1.2 | 1.6 ± 0.9 | 2.2 ± 1.3 | 1.6 ± 1.2 |
| Maternal age (years) | 22.2 ± 5.2 | 25.1 ± 5.3 | 26.3 ± 6.9 | 27.2 ± 6.1 |
| Maternal prepregnancy weight (kg) | 60.3 ± 15.0 | 59.9 ± 15.2 | 63.0 ± 11.3 | 58.1± 8.2 |
| Maternal height (cm) | 163 ± 8 | 163 ± 8 | 165 ± 5 | 165 ± 5 |
| Maternal smoking during pregnancy (%) | 42 | 48 | 36 | 48 |
| Maternal years of education | 11.2 ± 1.3 | 11.7 ± 1.6 | 10.9 ± 2.8 | 11.5 ± 1.9 |
| Family income at registration ($) | 3,929 ± 1,748 | 4,250 ± 2,192 | 4,976 ± 2,713 | 5,848 ± 2,673 |
| Socioeconomic index at registration | 50.2 ± 20.2 | 52.4 ± 20.2 | 53.7 ± 18.0 | 56.0 ± 13.7 |
Values are mean ± SD except where otherwise noted.