The nipple extrusion of clear water out, may be due to physiological factors and pathological factors, it is recommended to consult a doctor in a timely manner to identify the cause of the symptomatic treatment. 1. Physiological factors: If a woman is in physiological period or growth and development period, the secretion of estrogen in the body will increase, and the breast ducts appear to proliferate, so that the nipple extrusion of clear water or milky white liquid outflow, may be a normal physiological phenomenon, do not need special treatment. If the patient is breastfeeding, the clear water in the nipple may be light breast milk. 2. Pathological factors: If you are suffering from mastitis, intraductal papilloma, intraductal breast tumor and other diseases, it will also lead to the situation of clear water in the nipple extrusion, and it is recommended to consult a doctor in time for diagnosis and treatment. There are many reasons for nipple extrusion, when this situation occurs, it is recommended to go to the breast surgery of the local regular hospital in a timely manner, to clarify the cause of the disease, and then under the guidance of the doctor to carry out the relevant treatment.