Variables | Cases n (%) | Controls n (%) | Total n (%) | P value |
Total | 495 (100) | 478 (100) | 973 (100) | |
Age at menarche (years) | <0.001 | |||
≤12 | 93 (18.79) | 137 (28.66) | 230 (23.64) | |
13 | 115 (23.23) | 121 (25.31) | 236 (24.25) | |
14 | 121 (24.44) | 119 (24.9) | 240 (24.67) | |
15 | 72 (14.55) | 55 (11.51) | 127 (13.05) | |
≥16 | 94 (18.99) | 46 (9.62) | 140 (14.39) | |
Previously conceived | <0.001 | |||
Yes | 464 (93.74) | 371 (77.62) | 835 (85.82) | |
No | 31 (6.26) | 107 (22.38) | 138 (14.18) | |
Abortion history | 0.012 | |||
Yes | 243 (49.09) | 273 (57.11) | 516 (53.03) | |
No | 252 (50.91) | 205 (42.89) | 457 (46.97) | |
Menopause | <0.001 | |||
Yes | 374 (75.56) | 127 (26.57) | 501 (51.49) | |
No | 121 (24.44) | 351 (73.43) | 472 (48.51) | |
History of benign breast diseases | 0.201 | |||
Yes | 98 (19.80) | 91 (19.04) | 189 (19.42) | |
No | 360 (72.73) | 364 (76.15) | 724 (74.41) | |
Unknown | 37 (7.47) | 23 (4.81) | 60 (6.17) | |
Family history of breast cancer | 0.025 | |||
Yes | 44 (8.89) | 24 (5.02) | 68 (6.99) | |
No | 441 (89.09) | 442 (92.47) | 883 (90.75) | |
Unknown | 10 (2.02) | 12 (2.51) | 22 (2.26) |