Table 2 Odds ratios (OR) with 95% confidence intervals (CI) for breast cancer related to the use of oral contraceptives (OCs) while customer of the HSHS or before that.
From: Oral contraceptive use before first birth and risk of breast cancer: a case control study
OC user | Cases | Controls | Crude | Adjusted* | |||
|---|---|---|---|---|---|---|---|
n | % | n | % | OR | OR | 95% CI | |
No † | 15 | 10 | 57 | 18 | 1 | 1 | |
Yes | 114 | 76 | 222 | 70 | 2.1 | 2.1 | (1.1, 4.2) |
Not recorded | 21 | 14 | 37 | 12 | 1.9 | 1.6 | (0.6, 4.0) |
Total | 150 | 100 | 316 | 100 | |||