Table 5.

Factors related to breast cancer analyzed by univariate analysis

Variables	OR^a	95% CI	P -value
Body mass index	0,994	0,937 -1,05	0,849
Physical activity	0,507	0,339-0,757	0,001
Early age at menarche (<12 years)	2,474	1,354 -4,521	0,03
Oral contraceptive (>6 months)	1,716	0,696-4,232	0,005
Early childbearing (<30 years)	0,212	0,087-0,514	0,001
Multiparity	0,742	0,359-1,539	<0,001
Lactation (>6 months)	0,737	0,357-1,523	<0,001
Family history of breast First degree	11,556	2,548-52,411	0,002
Second degree	0,841	0,319-2,217	0,726
Exposure to irradiation	0,953	0,250-3,630	0,944

Odds ratio (OR) has been adjusted for age by univariate logistic regression. Significance threshold P < 0.05.CI : confidence interval