Prenatal DES exposure in relation to risk of invasive breast cancer among women ages ≥40 years according to parity, family history of breast cancer, use of female hormone supplements, use of oral contraceptives, and menopausal status
| . | Exposed . | . | Unexposed . | . | Age-adjusted IRR (95% CI) . | ||
|---|---|---|---|---|---|---|---|
| . | Person-years of follow-up . | Cases* . | Person-years of follow-up . | Cases* . | . | ||
| Parous | 19,290 | 43 | 9,941 | 14 | 1.98 (1.06-3.71) | ||
| Nulliparous | 9,901 | 17 | 3,100 | 3 | 1.72 (0.50-5.86) | ||
| Family history | 3,938 | 18 | 1,771 | 4 | 2.26 (0.74-6.91) | ||
| No family history | 24,899 | 42 | 11,156 | 13 | 1.83 (0.96-3.51) | ||
| Ever FH use | 6,677 | 20 | 3,137 | 8 | 1.69 (0.70-4.08) | ||
| Never FH use | 22,083 | 39 | 9,752 | 9 | 1.98 (0.96-4.10) | ||
| Never OC use | 6,088 | 12 | 2,468 | 1 | — | ||
| Ever OC use | 23,073 | 48 | 10,461 | 16 | 1.63 (0.91-2.94) | ||
| Premenopausal | 20,587 | 39 | 8,989 | 8 | 2.20 (1.02-4.72) | ||
| Postmenopausal | 6,383 | 17 | 2,974 | 7 | 1.87 (0.72-4.83) | ||
| . | Exposed . | . | Unexposed . | . | Age-adjusted IRR (95% CI) . | ||
|---|---|---|---|---|---|---|---|
| . | Person-years of follow-up . | Cases* . | Person-years of follow-up . | Cases* . | . | ||
| Parous | 19,290 | 43 | 9,941 | 14 | 1.98 (1.06-3.71) | ||
| Nulliparous | 9,901 | 17 | 3,100 | 3 | 1.72 (0.50-5.86) | ||
| Family history | 3,938 | 18 | 1,771 | 4 | 2.26 (0.74-6.91) | ||
| No family history | 24,899 | 42 | 11,156 | 13 | 1.83 (0.96-3.51) | ||
| Ever FH use | 6,677 | 20 | 3,137 | 8 | 1.69 (0.70-4.08) | ||
| Never FH use | 22,083 | 39 | 9,752 | 9 | 1.98 (0.96-4.10) | ||
| Never OC use | 6,088 | 12 | 2,468 | 1 | — | ||
| Ever OC use | 23,073 | 48 | 10,461 | 16 | 1.63 (0.91-2.94) | ||
| Premenopausal | 20,587 | 39 | 8,989 | 8 | 2.20 (1.02-4.72) | ||
| Postmenopausal | 6,383 | 17 | 2,974 | 7 | 1.87 (0.72-4.83) | ||
Abbreviations: FH, female hormone supplement; OC, oral contraceptives.
Case numbers do not sum to total because of missing data on covariates.