Nipple discharge refers to any fluid that seeps out of the nipple in a nonlactating woman. Nonmilk discharge comes out of your breasts through the same nipple openings that carry milk.

One or both breasts may produce a nipple discharge, either spontaneously or when you squeeze your nipples or breasts. A nipple discharge may look milky, or it may be clear, yellow, green, brown or bloody. The consistency of nipple discharge varies from thick and sticky to thin and watery.

Nipple discharge is a symptom that largely affects women. However, nipple discharge in a man under any circumstances is problematic and should be investigated.

Causes of Nipple Discharge

Sometimes, nipple discharge is just a normal (physiological) part of your breast’s function.  If that’s the case, the discharge might resolve on its own.  Most often, nipple discharge stems from a noncancerous (benign) condition.  However, breast cancer is a possibility, especially if:

– You are over age 40
– You have a lump in your breast
– The discharge contains blood
– Only one breast is affected
– The discharge occurs spontaneously (without squeezing)

Possible causes of nipple discharge include:

– Abscess
– Breast cancer
– Breast infection
– Excessive breast stimulation
– Fibroadenoma
– Fibrocystic breasts
– Ductal Carcinoma in Situ (DCIS)
– Galactorrhea
– Hormone imbalance
– Injury or trauma to the breast
– Intraductal papilloma
– Mammary duct ectasia
– Medication use
– Paget’s disease of the breast
– Pregnancy
– Prolactinoma

When to see a doctor

Rarely is nipple discharge a sign of breast cancer.  But it might be a sign of an underlying condition that requires treatment.  If you’re still having periods and your nipple discharge doesn’t resolve on its own after your next menstrual cycle, or if it’s bothersome, make an appointment with your doctor.  If you’re postmenopausal and experience nipple discharge any time, see your doctor right away.

In the meantime, avoid nipple stimulation – including frequent checks for discharge – because stimulation actually makes the discharge persist.