From: An investigation of breast cancer risk factors in Cyprus: a case control study
 | Before adjustment | After mutual adjustment | Fully adjusted4 | |||
---|---|---|---|---|---|---|
 | OR (95%CI) | p-value | OR (95%CI) | p-value | OR (95%CI) | p-value |
A. Pregnancy | Â | Â | Â | Â | Â | Â |
   No | 1.00 |  |  |  |  |  |
   Yes | 0.69 (0.49,0.97) | 0.03 | 0.89 (0.62,1.28) | 0.54 | 1.07 (0.66,1.72) | 0.79 |
   Breastfeeding 1 |  |  |  |  |  |  |
   No | 1.00 |  |  |  |  |  |
   Yes | 0.69 (0.57,0.82) | <0.001 | 0.63 (0.45,0.89) | <0.01 | 0.72 (0.59,0.90) | <0.01 |
   Breastfeeding by duration 1, 2 |  |  |  |  |  |  |
   Never | 1.00 |  |  |  |  |  |
   ≤6 months | 0.71 (0.58,0.88) |  | 0.65 (0.45,0.94) |  | 0.73 (0.57,0.93) |  |
   7-12 months | 0.76 (0.58,0.98) |  | 0.69 (0.47, 1.03) |  | 0.86 (0.64,1.16) |  |
   >1 year | 0.61 (0.48,0.77) | <0.0013 | 0.56 (0.38,0.81) | <0.0013 | 0.68 (0.51,0.91) | 0.043 |
B. Breastfeeding | Â | Â | Â | Â | Â | Â |
   No | 1.00 |  |  |  |  |  |
   Yes | 0.69 (0.57,0.83) | 0.03 | 0.72 (0.58,0.88) | <0.01 | 0.72 (0.58,0.90) | <0.01 |
   Number of children |  |  |  |  |  |  |
   None | 1.00 |  |  |  |  |  |
   One | 0.90 (0.59,1.37) |  | 1.06 (0.69,1.64) |  | 1.29 (0.76,2.18) |  |
   Two | 0.84 (0.61,1.15) |  | 1.04 (0.74,1.48) |  | 1.27 (0.76,2.18) |  |
   Three | 0.68 (0.49,0.94) | <0.013 | 0.90 (0.62,1.29) | 0.253 | 1.14 (0.82,1.99) | 0.87 |