Nipple discharge is a typical 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 usually affects 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:
- Abscess
- 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)
- Galactorrhea
- 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
- Prolactinoma
Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.
- Understanding breast changes: A health guide for women. National Cancer Institute. https://www.cancer.gov/publications/patient-education/understanding-breast-changes. Accessed Oct. 10, 2019.
- Golshan M. Nipple discharge. https://www.uptodate.com/contents/search. Accessed Oct. 10, 2019.
- Lee SJ, et al. ACR Appropriateness Criteria evaluation of nipple discharge. Journal of the American College of Radiology. 2017;14:S138.
- Nipple discharge. Merck Manual Professional Version. https://www.merckmanuals.com/professional/gynecology-and-obstetrics/breast-disorders/nipple-discharge. Accessed Oct. 10, 2019.
- AskMayoExpert. Nipple discharge. Mayo Clinic; 2019.
- Pruthi S (expert opinion). Mayo Clinic. Oct. 10, 2019.
- American College of Obstetricians and Gynecologists. Practice Bulletin No. 164: Diagnosis and management of benign breast disorders. Obstetrics & Gynecology. 2016; doi:10.1097/AOG.0000000000001482.
- Galactorrhea. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/pituitary-disorders/galactorrhea#v980911. Accessed Oct. 9, 2019.
- Paget disease of the breast. National Cancer Institute. https://www.cancer.gov/types/breast/paget-breast-fact-sheet. Accessed Oct. 10, 2019.
- Dixon JM. Nonlactational mastitis. https://www.uptodate.com/contents/search. Accessed Oct. 10, 2019.