Table 1.
Characteristics of women at baseline by menopausal status
| n | Premenopausal women | Postmenopausal women | ||
|---|---|---|---|---|
| 118,786 | 200,403 | |||
| Age at enrollment, mean, s.d | 43.7 | 5.1 | 60.6 | 8.1 |
| Body mass index, mean, s.d | 23.0 | 3.1 | 23.5 | 3.5 |
| Body mass index, n, % | ||||
| < 18.5 | 5,862 | 4.9% | 11,885 | 5.9% |
| 18.5- < 21 | 27,243 | 22.9% | 34,326 | 17.1% |
| 21- < 23 | 32,295 | 27.2% | 46,852 | 23.4% |
| 23- < 25 | 26,556 | 22.4% | 45,963 | 22.9% |
| 25- < 27.5 | 17,294 | 14.6% | 37,651 | 18.8% |
| 27.5- < 30 | 6,566 | 5.5% | 16,091 | 8.0% |
| 30- | 2,970 | 2.5% | 7,635 | 3.8% |
| Smoking status, n, % | ||||
| Never | 104,385 | 91.9% | 164,467 | 91.2% |
| Former | 1567 | 1.4% | 3678 | 2.0% |
| Current | 7598 | 6.7% | 12,198 | 6.8% |
| Alcohol consumption, n, % | ||||
| Non-drinkers | 87,553 | 76.1% | 150,976 | 81.5% |
| Current drinkers | 27,444 | 23.9% | 34,300 | 18.5% |
| Age at menarche (years), n, % | ||||
| ≤ 10 | 257 | 0.2% | 157 | 0.1% |
| 11–12 | 12,330 | 11.1% | 7778 | 4.4% |
| 13–14 | 52,410 | 47.3% | 52,241 | 29.5% |
| 15–16 | 35,427 | 32.0% | 71,843 | 40.5% |
| ≥ 17 | 10,330 | 9.3% | 45,165 | 25.5% |
| Nulliparity, n, % | ||||
| No | 108,760 | 94.0% | 174,919 | 92.3% |
| Yes | 6961 | 6.0% | 14,623 | 7.7% |
| Age at first delivery (years), n, % | ||||
| ≤ 20 | 4992 | 4.7% | 23,160 | 13.6% |
| 21–25 | 49,110 | 45.8% | 93,919 | 55.3% |
| 26–30 | 43,940 | 41.0% | 43,971 | 25.9% |
| ≥ 31 | 9134 | 8.5% | 8786 | 5.2% |
| Age at menopause (years), n, % | ||||
| ≤ 44 | 27,861 | 16.0% | ||
| 45–49 | 62,059 | 35.5% | ||
| 50–54 | 75,850 | 43.4% | ||
| ≥ 55 | 8818 | 5.1% | ||
s.d. standard deviation