Category of benign breast disease | |||
---|---|---|---|
Descriptive characteristic | Nonproliferative | Proliferative without atypia | Atypical hyperplasia |
Mean | |||
Age at biopsy (y) | 42.5 | 43.7 | 50.1 |
Year of biopsyb | 1979 | 1980 | 1983 |
Age at menarche (y) | 12.7 | 12.5 | 12.9 |
Age at first birthc (y) | 24.8 | 24.9 | 25.0 |
Age at menopaused | 46.6 | 46.5 | 47.2 |
Body mass index, kg/m2 | 25.1 | 24.6 | 24.5 |
Parity | 2.8 | 2.7 | 2.9 |
Recent alcohol consumption, g/day | 4.8 | 5.4 | 6.6 |
Frequency, % | |||
Premenopausal at biopsy | 76.5 | 76.1 | 57.1 |
Family history of breast cancer | 11.2 | 13.3 | 18.3 |
Nulliparous | 6.5 | 8.2 | 5.6 |
Natural menopause d | 46.8 | 50.7 | 48.5 |
Bilateral oophorectomyd | 20.1 | 16.8 | 17.5 |