Fig. 1: Associations of hormones and SHBG with the risk of invasive breast cancer by age at blood collection in pre-menopausal women.

Hazard ratios stratified for age group, region and deprivation; adjusted for age (underlying time variable), ethnicity, educational level, smoking, alcohol, physical activity, BMI, regular menstrual cycle, parity, age at first birth, time since OCP use, presence of endocrine disorders, family history of breast cancer and other hormones and SHBG; and corrected for regression dilution using repeat measures except for total and calculated free oestradiol.