Nipple discharge is a normal part of breast function during pregnancy or breast-feeding. It may also 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. The discharge associated with a papilloma often occurs spontaneously and involves a single duct. Although the bloody discharge may resolve on its own, your doctor will likely recommend a diagnostic mammogram and a breast ultrasound to see what's causing the discharge. You may also need a biopsy to confirm that it's a papilloma or to exclude a cancer. If the biopsy confirms a papilloma, your doctor will refer you to a surgeon to discuss treatment options.
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 or is clear
- 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 (lumpy or rope-like breast tissue)
- Injury or trauma to the breast
- Intraductal papilloma (a benign, wartlike growth in a milk duct)
- Mammary duct ectasia
- Medication use
- Menstrual cycle hormone changes
- Paget's disease of the breast
- Periductal mastitis
- Pregnancy and breast-feeding
Dec. 03, 2019
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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