Table 1. Participant characteristics at recruitment.
| Number of women |
1 300 101 |
|
| Age in years—mean (s.d.) | 56.1 | 4.9 |
| N | % | |
| Body mass index >30 | 220 986 | 17.0 |
| Ever used oral contraceptives | 761 728 | 58.6 |
| Ever smokers | 596 284 | 45.9 |
| Parous | 1 157 243 | 89.0 |
| Three or more children | 427 331 | 32.9 |
| History of tubal ligation | 289 634 | 22.3 |
| Hysterectomy | 316 944 | 24.4 |
| Postmenopausal, never HT user | 424 872 | 32.7 |
| Ever used hormone therapy | 644 831 | 49.6 |
| Most deprived quintile | 255 619 | 19.7 |
| Prior cervical intraepithelial neoplasia grade 3 registration | 12 531 | 1.0 |
Abbreviation: HT=hormone therapy.