If you are not pregnant but have breast milk, you need to consider that it is caused by the following conditions: 1. If you have breast milk in unilateral breast, if the amount of milk is not much, it may be caused by unilateral breast enlargement, there will be breast overflow, breast pain, lumps, etc., especially before menstruation, the symptoms are more obvious, you need to carry out medication or surgery. 2. If you have breast milk in both breasts. Most of them are caused by pathological reasons, and are considered to be caused by pituitary tumors that lead to disorders of prolactin secretion. Hyperprolactinemia can also lead to irregular menstruation, and in severe cases, headaches, weight gain, amenorrhea, infertility, and atrophy of the external genitalia, and other symptoms that require prompt treatment. Therefore, once there is breast milk without pregnancy, it is best to go to the hospital for further examination and targeted treatment in a timely manner.