Although there was little evidence for association of ABSI with breast cancer overall (hazard ratio HR = 0.984; 95% confidence interval: 0.961–1.007), we found borderline inverse associations for post-menopausal women (HR = 0.971; 0.942-1.000; n = 5268 cases) and breast cancers diagnosed at age ≥ 55 years (HR = 0.976; 0.951–1.002; n = 7043) and clear inverse associations for ER + PR- subtypes (HR = 0.894; 0.822–0.971; n = 726) and ER-PR- subtypes (HR = 0.906; 0.835–0.983 n = 759). This evidence concerns the gene PGR and breast carcinoma.