| Birth year | |||||
|---|---|---|---|---|---|
| <1970 | 1970–1972 | 1973–1975 | 1976–1978 | >1978 | |
| Mean age at menarche in years (SD) | 13.41 (1.30) | 13.31 (1.29) | 13.19 (1.30) | 13.10 (1.27) | 13.03 (1.28) |
| % having ever smoked | 23.55 | 19.47 | 22.74 | 27.14 | 32.86 |
| % having ever used oral contraceptives | 25.49 | 23.05 | 29.31 | 30.43 | 31.24 |
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