CausesBy Mayo Clinic Staff
Nipple discharge is a normal part of breast function during pregnancy or breast-feeding. It also may be associated with menstrual hormone changes and fibrocystic changes. The milky discharge after breast-feeding will normally affect both breasts and can continue for up to two or three years after stopping nursing.
A papilloma is a noncancerous (benign) tumor that can be associated with bloody discharge. It appears spontaneously and involves a single duct. Although the bloody discharge may resolve on its own, this situation requires evaluation with an ultrasound of the area behind the nipple and areola. If the ultrasound shows a lesion within a milk duct, you may need a biopsy to confirm that it's a papilloma or to exclude a cancer.
Often, nipple discharge stems from a benign condition. However, breast cancer is a possibility, especially if:
- You have a lump in your breast
- Only one breast is affected
- The discharge contains blood
- The discharge is spontaneous and persistent
- The discharge affects only a single duct
Possible causes of nipple discharge include:
- Birth control pills
- Breast cancer
- Breast infection
- Ductal carcinoma in situ (DCIS)
- Endocrine disorders
- Excessive breast stimulation
- Fibrocystic breasts
- Injury or trauma to the breast
- Intraductal papilloma
- Mammary duct ectasia
- Medication use
- Menstrual cycle hormone changes
- Paget's disease of the breast
- Periductal mastitis
- Pregnancy and breast-feeding
Dec. 10, 2016
Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.
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