|
Odds ratios (OR) with 95% confidence intervals (CI) for breast cancer associated with use of oral contraceptives (OCs) in relation to the first birth‡. |
|||||
| Use of OC |
Cases |
Controls |
Crude |
Adjusted* |
|
| n |
n |
OR |
OR |
95% CI |
|
|
|
|||||
| User after 1st birth † |
7 |
12 |
0.8 |
0.8 |
(0.2, 2.5) |
| User before 1st birth |
74 |
143 |
1.1 |
1.0 |
(0.5, 1.7) |
| User, no births |
32 |
62 |
1 |
1 |
|
| Order of use and births** not known |
1 |
5 |
|||
|
‡ Women missing information about OC use or (21 cases and 37 controls) or having not used OCs while in the HSHS (15 cases and 57 controls) were excluded. *Adjusted for sports (no sports, sports, unknown) and smoking (never, ever, unknown). † Reference group. **Chronological order of the first delivery and start of OC use. | |||||
Hemminki et al. BMC Women's Health 2002 2:9 doi:10.1186/1472-6874-2-9 |
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