Health Conditions A-Z Cancer Breast Cancer 5 Causes of Nipple Discharge By Ashley Abramson Ashley Abramson Ashley Abramson is a freelance writer based in Milwaukee, WI. She's written for the New York Times, Washington Post, The Guardian, and more. health's editorial guidelines Updated on March 24, 2024 Medically reviewed by Cordelia Nwankwo, MD Medically reviewed by Cordelia Nwankwo, MD Cordelia Nwankwo, MD, is a board-certified gynecologist who has been in private practice for 8 years. learn more Ariel Skelley / Getty Images Nipple discharge refers to fluid leaks coming from either or both breast nipples, which can happen during pregnancy and breastfeeding. It's also normal for around 50% to 80% of people with breasts who aren't pregnant or breastfeeding to experience discharge from their nipples. Nipple discharge may not be problematic if it's milky, yellow, or green, or if it's due to factors like a recent stop with breastfeeding. You may want to see a healthcare provider, however, if you have abnormal discharge like bloody discharge. Here's what you should know. What Is Normal Discharge? Normal discharge is usually non-spontaneous. That means someone has to elicit the discharge themselves. It comes from both breasts and can come out of multiple ducts. Green, milky, yellow, or white nipple discharge may occur but still be considered normal. This kind of discharge can also be due to various causes. Causes Milky discharge can come out with nipple stimulation if people recently breastfed but stopped. The discharge can also occur during pregnancy or for a year after birth. There's another condition called galactorrhea, in which people produce milk when they're not breastfeeding. This happens as the result of an unnecessarily increased release of prolactin, a hormone with a role in breast milk production. Nipple discharge can also be a medication side effect. People may create and leak milk even when they're not breastfeeding and haven't recently with medications such as: Antidepressants Antihypertensives for blood pressure Antipsychotics Opioids Oral contraceptives, or birth control What Is Abnormal Discharge? On the other hand, pathologic—or abnormal—discharge may stem from something inside the breast. Medically concerning discharge comes from just one breast or a single duct in that breast. It also tends to be spontaneous, which means it comes out on its own without nipple stimulation. Bloody or brown discharge and discharge that looks like serum are additional signs of abnormal discharge. Causes Intraductal papillomas are a common cause of abnormal discharge. They are cauliflower-like masses in the breast ducts that are typically non-cancerous. Ductal ectasia, another benign condition of the breast, may result in abnormal discharge. It is the result of a widened milk duct with thickened walls. Nipple Discharge and Breast Cancer Most nipple discharge isn't normally associated with breast cancer. In some cases, clear or bloody nipple discharge can be a symptom of breast cancer. While bloody discharge should generally prompt people to visit a healthcare provider, it's not always something growing inside the breast. For example, a person may have bloody nipple discharge when breastfeeding due to increased blood flow after the body begins to make milk. When To Contact a Healthcare Provider A healthcare provider can help you determine the cause if you have concerning nipple discharge. They'll ask questions about your symptoms as well as your medical history to learn more about possible causes for the discharge. If they're concerned it could be pathologic, they may send you for a breast exam. Breast imaging, like an MRI, can show a provider your breast ducts so they can determine if there's a mass. Updated Screening Guidelines In 2024, the U.S. Preventive Services Task Force (USPSTF) released new guidelines recommending that women get screened for breast cancer every other year between the ages of 40 and 74. Some women may need an annual screening, especially if you're at a higher risk of breast cancer or if you have dense breast tissue. A Quick Review Nipple discharge is normal in some cases, such as if someone has recently stopped breastfeeding or if they have galactorrhea. Abnormal nipple discharge may be the result of conditions like intraductal papilloma or duct ectasia. It's important to be aware of the different types of nipple discharge so you can take care of your health. Seeing a healthcare provider can help you figure out more about discharge causes and whether your discharge is normal. Frequently Asked Questions When should I be concerned about nipple discharge? Discharge is more concerning if it's bloody, leaks out of one breast, or has both of those characteristics. Is it okay to squeeze out nipple discharge? No. Even if you're checking for discharge, it's best not to squeeze your nipple. How is nipple discharge treated? Nipple discharge treatments depend on the cause. For example, you may need to change medications with nipple discharge as a side effect or have breast ducts removed. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit 11 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Sajadi-Ernazarova KR, Sugumar K, Adigun R. Breast nipple discharge. In:StatPearls. StatPearls Publishing; 2023. Stafford AP, Cruz LMDL, Willey SC. Workup and treatment of nipple discharge—a practical review. 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