Table 1 Characteristics of primipara, by plant
| Â | Â | Indiana Plant (n = 173) | Massachusetts Plant (n = 1481) | New York Plant (n = 941) |
|---|---|---|---|---|
PCB production years a | 1957-1977 | 1938-1977 | 1948-1977 | |
Estimated cumulative occupational PCB exposure, to estimated date of conception b | Â | Â | Â | |
| Â | Median | 4,868 | 193,320 | 20,988 |
| Â | Interquartile range | 2,460-8,510 | 84,672-397,512 | 8,700-54,120 |
Duration of employment (years), prior to estimated date of conception c | Â | Â | Â | |
| Â | Median | 2.0 | 2.6 | 2.0 |
| Â | Interquartile range | 1.1-2.7 | 1.3-4.6 | 1.1-3.5 |
Occupationally PCB exposed prior to estimated date of conception (n, %) | 86 (49.7%) | 1,034 (69.8%) | 386 (41.0%) | |
Reproductive history reported by proxy | 2 (1.2%) | 190 (12.8%) | 82 (8.7%) | |
Gender of offspring (n, %) | Â | Â | Â | |
| Â | Males | 85 (49.1%) | 724 (48.9%) | 484 (51.4%) |
| Â | Females | 88 (50.9%) | 757 (51.1%) | 457 (48.6%) |
Maternal race/ethnicitiy (n, %) | Â | Â | Â | |
| Â | White, non-Hispanic | 165 (95.4%) | 1,234 (83.3%) | 914 (97.1%) |
| Â | Non-white or multiracial | 8 (4.6%) | 247 (16.7%) | 27 (2.9%) |
Maternal education (n, %) | Â | Â | Â | |
| Â | Grade school only | 1 (0.6%) | 125 (8.6%) | 7 (0.8%) |
| Â | Some high school | 9 (5.2%) | 477 (32.7%) | 98 (10.5%) |
| Â | High school graduate or GED | 69 (39.9%) | 522 (35.8%) | 537(57.3%) |
| Â | Some college or professional training | 75 (43.4%) | 261 (17.9%) | 229(24.4%) |
| Â | College degree or higher | 19 (11%) | 74 (5.1%) | 67 (7.1%) |
Maternal Age (n, %) | Â | Â | Â | |
| Â | 18 or younger | 30 (17.3%) | 141 (9.5%) | 147 (15.6%) |
| Â | 19-24 | 100 (57.8%) | 910 (61.4%) | 550 (58.5%) |
| Â | 25-29 | 29 (16.8%) | 286 (19.3%) | 156 (16.6%) |
| Â | 30 or older | 14 (8.1%) | 144 (9.7%) | 88 (9.4%) |