Nipple discharge, fluid coming from the nipple(s), is the third most common breast complaint for which women seek medical attention, after lumps and breast pain. The majority of nipple discharges are associated with non-cancerous changes in the breast such as hormonal imbalances or papillomas (non-cancerous, polyp-like tumor that grows inside the breast duct). However, because a small percentage of nipple discharges can indicate breast/nipple cancer, any persistent discharge from the nipple(s) should be evaluated by a physician.
Milky discharge (cloudy, whitish or almost clear in color, thin, non-sticky) is the most common type of discharge. Most milky discharge is caused by lactation or increased stimulation. Most bloody or watery (serous) nipple discharge is due to a benign papilloma, infection, or possibly cancer. Discharges that are yellow, green, blue, or black in color are often associated with benign cysts. Bilateral nipple discharge (discharge occurring from both breasts) is usually benign and does not typically require investigation. Discharge caused by a malignant condition is almost always on one side only (unilateral).
Nipple discharge is of concern if it is:
- Bloody or watery (serous).
- Appears spontaneously without squeezing the nipple or breast.
- On one side only (unilateral)