Table 1.
Mean (SD), median or percentage (n) | |
---|---|
Percent mammographic density | 25 (18.1), 21.9 |
BMI at age 53 (kg/m2) (n = 1,124)a | 27.6 (5.48), 26.5 |
Age at mammography in years (n = 1,130)a | 51.5 (1.1), 51.5 |
Age at menarche | |
<12 | 13% (151) |
12 | 22% (255) |
13 | 28% (325) |
14+ | 16% (186) |
Missing | 22% (244) |
Menopausal status at the time of mammography | |
Pre-menopause | 17% (197) |
Peri-menopause | 17% (197) |
Post-menopause | 24% (279) |
Hysterectomy | 19% (221) |
HRT/oral contraceptive pill | 18% (209) |
Unknown | 5% (58) |
History of hormone therapy use | |
Never | 54% (627) |
Ever | 46% (534) |
Parity | |
0 | 12% (139) |
1 | 11% (128) |
2 | 45% (512) |
3 | 22% (255) |
4+ | 8% (93) |
Missing | 2% (23) |
Smoking status at age 53 | |
Current smoker | 21% (244) |
Non-smoker | 77% (894) |
Missing | 2% (23) |
Level of physical activity at age 53 | |
Nil | 48% (557) |
Moderate | 16% (186) |
High | 34% (395) |
Missing | 2% (23) |
an varies due to missing data