Nipple Discharge

The breast contains a network of milk ducts that converge at the nipple. Even in women who are not pregnant or nursing, these ducts can produce small amounts of fluid. Many women notice discharge only when the nipple is squeezed; this kind of discharge, especially if it comes from both breasts and multiple ducts, is rarely a cause for concern. What prompts closer evaluation is discharge that appears spontaneously (without squeezing), comes from a single duct in one breast, or has a bloody or clear watery appearance.

The most common causes of non-lactational nipple discharge are benign. A small, non-cancerous growth in a duct called an intraductal papilloma is one of the most frequent culprits, often producing a discharge that is clear, serous (straw-colored), or bloody. Fibrocystic changes, infections, and certain medications — including antidepressants, antipsychotics, and blood pressure drugs — can also cause discharge. Elevated prolactin levels, a pituitary gland hormone, are another non-breast cause worth investigating.

Evaluation typically involves a physical exam, review of medications, and imaging — often a mammogram and ultrasound. In some cases, ductography (imaging of the duct system with contrast) or a minimally invasive procedure called a ductoscopy or duct excision may be recommended. Biopsy is used to evaluate any solid area or mass identified during imaging.

Noticing discharge from your nipple can understandably cause alarm, but the most important thing to know is that the majority of nipple discharge cases turn out to have a benign cause. What matters is describing the discharge accurately to your doctor — which breast, which part of the nipple, what color, and whether it appears on its own or only when you squeeze.

Spontaneous, bloody, or single-duct discharge in one breast deserves prompt evaluation — not because it is necessarily cancer, but because identifying the cause allows for appropriate treatment and peace of mind. Most of the time, the source turns out to be an intraductal papilloma or other benign condition that can be managed with a straightforward procedure. Getting it checked promptly means you get an answer sooner.