Because your breast is a gland, your nipples may occasionally secrete fluids, even if you’ve never been pregnant. Cancer is rarely the underlying cause, but other conditions that require treatment may be. To find the cause, you’ll need to see your doctor.
What is nipple discharge?
Unless you’re lactating, fluid seeping out of your nipple is referred to as nipple discharge. Non-milk discharge comes out of your breasts through the same nipple openings that carry milk. On each of your nipples is a cluster of about ten of these openings.
One or both breasts may produce a nipple discharge, either spontaneously or when you squeeze your nipples or breasts. A nipple discharge may look milky, or it may be yellow, green, brown or bloody. The consistency of nipple discharge varies from thick and sticky to thin and watery.
Your chances of having nipple discharge increase as you get older and with the number of pregnancies you’ve had.
Your doctor’s assessment
When you go to a doctor to have nipple discharge checked out, you’ll need to give a detailed description of what’s going on. Specifically:
- What color is the discharge?
- How much discharge is there?
- Does it happen in one or both breasts?
- Does the discharge appear to come from one opening in your nipple or multiple openings?
- Is the discharge spontaneous, or does it happen only when you squeeze your nipple?
- Do you have any other signs and symptoms, such as fever, redness, pain in the breast, headaches or vision changes?
- Have you recently experienced an injury to the chest?
- What medications do you take?
Based on this information and a physical exam, you might need additional testing to help pinpoint the underlying cause. Such testing might include a blood test, mammography, a breast ultrasound, a special type of X-ray (ductogram) or magnetic resonance imaging (MRI). Your doctor might collect a sample of the fluid to send to a lab for analysis. However, even after lab analysis, further evaluation may be necessary.
Possible causes
Nipple discharge might just be a normal (physiological) part of your breast’s function. If that’s the case, the discharge might resolve on its own. Avoid nipple stimulation — such as by frequently checking for discharge — because stimulation actually makes the discharge persist.
Beyond normal, physiological functioning, other possible causes of nipple discharge include:
- Mammary duct ectasia. Mammary duct ectasia is one of the most common causes of abnormal nipple discharge. One or more of the ducts beneath your nipple becomes inflamed and clogged with a thick, sticky, green or black substance. Most often, mammary duct ectasia affects women in their 40s and 50s. You can relieve some of your symptoms by applying warm compresses to your breast. Taking aspirin or nonsteroidal anti-inflammatory drugs, such as ibuprofen, may help relieve some symptoms. Also, your doctor may prescribe antibiotics to clear up any infection. In some cases, surgery might be necessary to remove the affected duct.
- Intraductal papilloma. Intraductal papilloma is a small, usually noncancerous (benign) growth that projects into a milk duct near your nipple. It occurs most often in women between the ages of 35 and 55. Nobody knows what causes intraductal papillomas, and there are no known risk factors.
The discharge may be bloody or sticky and usually occurs spontaneously from one duct only, with manipulation of your nipple. You may notice staining or spotting from the discharge on your shirt or the inside of your bra. You may also feel a small lump behind and near the edge of your nipple (areola).
Your doctor may perform an ultrasound on your areola and the surrounding area to check for a nodule in a duct. Treatment involves surgical removal of the involved duct and examination of the tissue to rule out cancer.
- Galactorrhea. The nipple discharge associated with galactorrhea is usually white or clear, but it could be yellow or green, and it may leak from one or both breasts. Galactorrhea occurs because your body is making too much prolactin — the hormone your brain produces to stimulate milk production after you have a baby. This also might happen if you have a hormonal imbalance, such as from taking birth control pills; an underactive thyroid gland; a tumor (prolactinoma) or other disorder of the pituitary gland; or chronic breast stimulation, such as from frequent breast self-exams or sexual activity.
- Injury. A blunt trauma — for instance, the impact of the steering wheel in a car accident or a hard blow to your chest during sports — can cause nipple discharge in both your breasts. The nipple discharge results from tissue damage and may be clear, yellow or bloody. The discharge often occurs spontaneously and involves multiple ducts.
- Abscess. Most common in lactating women, a breast abscess can happen when your nipples become irritated or infected from breast-feeding. A break or crack in your skin can allow bacteria to invade your breast tissue, causing an infection. The nipple discharge may contain pus, and the breast can become red, swollen and warm to the touch. Treatment involves surgically draining the abscess, and your doctor also may prescribe antibiotics.
- Fibrocystic changes. Fibrocystic breast changes result in lumpy, tender breasts and can produce a clear, yellow or light green discharge from your nipples. Fibrocystic changes are very common, occurring to varying degrees in about half of all women. Your doctor may run some tests — such as a mammogram or an ultrasound — to make sure the discharge isn’t caused by cancer. If the tests show fibrocystic changes as the underlying cause, no further treatment is necessary.
- Breast cancer. Nipple discharge rarely is a sign of breast cancer, but it’s possible that discharge may indicate cancer is present within a duct (intraductal breast cancer) or outside the duct (invasive breast cancer). See your doctor promptly for evaluation if your discharge is bloody, spontaneous and occurs in only one breast.
Another form of cancer — Paget’s disease of the breast — also is associated with nipple discharge. Paget’s disease of the breast is uncommon, occurring in only 1 percent to 4 percent of all women with breast cancer. Signs and symptoms include itching, burning, redness or scaling of the nipple and areola — the darker colored skin surrounding the nipple. You may also have a bloody discharge from the nipple, and the nipple may appear flattened against your breast. Your doctor can diagnose the disease by doing a biopsy of the affected area of the areola. Standard treatment is removal of the breast (mastectomy), but removal of just the breast tumor (lumpectomy) may sometimes be an option. Your doctor might recommend chemotherapy or radiation after surgery.