Progesterone may cause breast nodules to enlarge in size. Breast nodules are usually caused by disorders of hormone levels in the body, which leads to benign hyperplasia of the breast. When progesterone is increased, the hormones in the body are changed, and at the same time, it can cause breast development and enlargement and breast nodule hyperplasia. Patients may experience symptoms such as a diffuse nodular sensation in the breast, accompanied by tenderness. If breast nodules appear after pregnancy, patients can first go to the hospital for relevant examinations to clarify the nature of the nodules, benign nodules can be observed regularly, while malignant nodules require immediate surgery, and regular review in the hospital to monitor the changes. Avoid overwork and fatigue, take appropriate exercise to improve immunity and keep breast clean. Eat a reasonable diet to improve nutrition, eat more vegetables, fruits, fresh fish, dairy products and other foods. Prohibit spicy stimulation, raw and cold food. It is recommended that patients with breast nodules go to the hospital for diagnosis and treatment in time, keep a good mood, and exercise appropriately.