Nipple discharge is any fluid that leaks from one or both nipples. It is normal during pregnancy and when breastfeeding. Some women may experience a milky white discharge from the nipples for up to three years after breastfeeding, which is usually normal. Nipple discharge may also be due to hormonal changes and fibrocystic breast changes. 

Causes of nipple discharge 

There are many cause of nipple discharge in addition to pregnancy and breastfeeding. They include:

  • breast cancer 
  • ductal carcinoma in situ (DCIS)
  • abscess or infection
  • hormone replacement therapy and hormonal birth control
  • excessive breast stimulation
  • fibrocystic breast changes, such as breast lumps, breast cysts, and breast pain
  • injury or trauma to the breast
  • intraductal papilloma
  • galactorrhea
  • hormonal changes during the menstrual cycle
  • medications
  • mammary duct ectasia
  • paget’s disease of the breast
  • mastitis and periductal mastitis
  • prolactinoma

Most causes of nipple discharge are benign (non-cancerous). The most common cause of nipple discharge is iuntraductal papilloma, a small, benign tumor in the milk duct. This condition is likely to cause bloody discharge from the nipple. 

All nipple discharge that is not related to pregnancy or breastfeeding should be evaluated by a doctor. Most causes of nipple discharge are not cancer. In fact, about 90 percent of people who experience abnormal nipple discharge do not have cancer. However, if you have other signs and symptoms of breast cancer along with nipple discharge, your chances of having breast cancer are increased. Some of those signs and symptoms to look for are:

  • a lump in the breast
  • nipple discharge is only from one breast
  • bloody or pink discharge
  • the nipple discharge is spontaneous (it happens without nipple stimulation) and persistent (it happens regularly)

Nipple discharge should also be evaluated if:

  • it occurs in women over 40
  • it occurs in men or boys

When should you see a doctor?

If you have nipple discharge outside of pregnancy and breastfeeding and it lasts for more than four weeks or you have any of the above symptoms, you should see your doctor within a week. If you have signs of infection along with the nipple discharge, such as redness, swelling, pus-like discharge, or a fever, you should be evaluated within a day or two at most. 

For a referral to a Beaumont breast care doctor, call 800-633-7377.