Table 2.
Reproductive characteristics and medical history of Black women aged 40-75 years in the WCHS, overall and by initial mode of breast cancer detection.
| Overall | Screening mammogram | Clinical breast exam | Self-detection | P-value | |
|---|---|---|---|---|---|
| (N = 1322) | (n = 725) | (n = 63) | (n = 534) | ||
| N (%) | n(%) | n(%) | n(%) | ||
| Menopausal status | <0.0001 | ||||
| Premenopausal | 516 (39.0) | 203 (28.0) | 36 (57.1) | 277 (51.9) | |
| Postmenopausal | 806 (61.0) | 522 (72.0) | 27 (42.9) | 257 (48.1) | |
| Age at menarche (years) | 0.324 | ||||
| <12 | 381 (28.8) | 212 (29.2) | 11 (17.5) | 158 (29.6) | |
| 12-13 | 618 (46.8) | 338 (46.6) | 32 (50.8) | 248 (46.4) | |
| >13 | 323 (24.4) | 175 (24.1) | 20 (31.8) | 128 (24.0) | |
| Parity | 0.428 | ||||
| Nulliparous | 231 (17.5) | 117 (16.1) | 9 (14.3) | 105 (19.7) | |
| 1-2 children | 679 (51.4) | 377 (52.0) | 31 (49.2) | 271 (50.8) | |
| ≥3 children | 412 (31.2) | 231 (31.9) | 23 (36.5) | 158 (29.6) | |
| Age at first birth (years)a | 0.605 | ||||
| <25 | 687 (63.0) | 382 (62.8) | 30 (55.6) | 275 (64.1) | |
| 25-30 | 242 (22.2) | 130 (21.4) | 15 (27.8) | 97 (22.6) | |
| >30 | 162 (14.9) | 96 (15.8) | 9 (16.7) | 57 (13.3) | |
| History of breastfeedinga | 0.458 | ||||
| No | 592 (54.5) | 336 (55.5) | 32 (59.3) | 224 (52.3) | |
| Yes | 495 (45.5) | 269 (44.5) | 22 (40.7) | 204 (47.7) | |
| History of oral contraceptive use | 0.685 | ||||
| No | 933 (70.6) | 505 (69.7) | 42 (66.7) | 386 (72.3) | |
| Yes | 388 (29.4) | 219 (30.2) | 21 (33.3) | 148 (27.7) | |
| History of hormone therapy use | <0.0001 | ||||
| No | 1084 (82.0) | 556 (76.7) | 57 (90.5) | 471 (88.2) | |
| Yes | 231 (17.5) | 166 (22.9) | 6 (9.5) | 59 (11.1) | |
| Family history of breast cancer | 0.733 | ||||
| No | 1075 (81.3) | 584 (80.6) | 52 (82.5) | 439 (82.2) | |
| Yes | 247 (18.7) | 141 (19.5) | 11 (17.5) | 95 (17.8) | |
| Body mass index (kg/m2) | <0.001 | ||||
| <25.0 | 261 (19.7) | 105 (14.5) | 16 (25.4) | 140 (26.2) | |
| 25.0-29.99 | 389 (29.4) | 226 (31.2) | 17 (27.0) | 146 (27.3) | |
| 30.0-34.99 | 312 (23.6) | 189 (26.1) | 14 (22.2) | 109 (20.4) | |
| ≥35.0 | 359 (27.2) | 204 (28.1) | 16 (25.4) | 139 (26.0) |
aAge at first birth and history of breastfeeding data are among parous women only.