The LIPG-breast cancer association was restricted to non-postpartum breast cancer (Multivariable OR for the highest LIPG category (95% CI) 3.83 (1.37–11.39), P-trend = 0.003, and 2.35 (0.16–63.65), P-trend = 0.396, for non-postpartum and postpartum breast cancer, respectively), although we lacked precision for postpartum breast cancer. Here, LIPG is linked to breast cancer.