Table 1. Characteristics of study participants (N = 32,584).
| Variable | Cases (n= 10,891) | Controls (n= 21,693) |
|---|---|---|
| Age at diagnosis/interview(y), mean (SD) | 58.1 (11.4) | 56.1 (24.9) |
| History of pregnancy | ||
| Yes | 6021 (80.4) | 15190 (87.9) |
| No | 1318 (17.6) | 1868 (10.8) |
| Unknown | 149 (2.0) | 217 (1.3) |
| Oral contraceptive use | ||
| Ever | 4017 (57.4) | 10572 (63.3) |
| Never | 2864 (41.0) | 5900 (35.3) |
| Unknown | 112 (1.6) | 243 (1.5) |
| Histology | ||
| Serous | 6500 (59.7) | NA |
| Mucinous | 696 (6.4) | |
| Endometrioid | 1439 (13.2) | |
| Clear Cell | 660 (6.1) | |
| Mixed Cell | 369 (3.4) | |
| Other or unknown epithelial type | 1227(11.3) | |
| Stage | ||
| Localized | 1425 (15.7) | NA |
| Regional | 1838 (20.2) | |
| Distant | 5721 (63.0) | |
| Unknown | 103 (1.1) | |
| Grade | ||
| I/II | 2882 (32.8) | NA |
| III/IV | 5174 (58.9) | |
| Other/Unknown | 729 (8.3) |