Table 2.

Odds ratio (OR) of different risk factors by univariate and multivariate regression analysis

	Univariate analysis, crude OR (CI 95%)	Multivariate analysis, adjusted OR(CI95%)
History of infertility	2.54 (1.06–6.08)	0.48 (0.1–2.29)
History of cancer in first-degree relatives	2.12 (1.01–4.47)	1.07 (0.22–5.24)
History of other cancers in the patient her/himself	1.09 (1.03–1.14)	0 (0.00–0.00)
History of benign lesion in the breast	4.73 (1.01–22.34)	0 (0.00–0.00)
History of radiotherapy to head/neck and chest	6.39 (2.14–19.17)	0.13 (0.01–1.26)
Age at marriage	1.07 (1.01–1.13)	1.17 (1.03–1.33)
Age at menopause	0.92 (0.84–0.99)	0.92 (0.84–1.01)

CI = Confidence interval.