Avoiding milk for a year and a half and still squeezing out yellow water may be caused by residual milk, breast hyperplasia, polycystic ovary syndrome and other factors. It is recommended that the patient go to the hospital in time to clarify the cause of the disease and then treated. 1. residual milk: generally in the weaning, did not take drugs or not timely emptying of the breast caused by, if the yellow water, no other symptoms, there is no need for treatment, the residual milk can be squeezed out, pay attention to local hygiene to avoid infection. 2. Mammary gland hyperplasia: a common benign breast disease, mainly related to endocrine disorders, estrogen and progesterone ratio imbalance leading to mammary gland hyperplasia. It causes the patient to avoid milk for a year and a half and still be able to squeeze out yellow water, but also accompanied by breast pain, lumps, fever and other symptoms. 3. polycystic ovary syndrome: the exact cause is still unclear, polycystic ovary syndrome will lead to hormonal disorders in the body, so that prolactin secretion increased, so that the patient avoided the milk for a year and a half can still squeeze out the yellow phenomenon, some patients accompanied by acne, alopecia, menstruation and other symptoms. It is recommended to pay attention to diet, avoid spicy, high-calorie food intake, maintain a happy mood, avoid exertion.