OR (95% CI) of breast cancer in premenopausal women according to ever use of hormone contraceptive, and in postmenopausal women according to ever use of hormone replacement therapy, stratified by BMI.

Adjusted for: age, socioeconomic status (high/medium/low), BMI (kg/m2), familial history of breast cancer in first degree relatives (yes/no), diabetes(yes/no), number of full term pregnancy, age at first full term pregnancy (years), total duration of breast feeding (months) and age at menarche (years)