Lactation is the process of producing breast milk. For women who are pregnant or recently gave birth, lactation is normal. Hormones signal the mammary glands in your body to start producing milk to feed the baby. But it’s also possible for women who have never been pregnant — and even men — to lactate. This is called galactorrhea, and it can happen for a variety of reasons.
Galactorrhea happens to around 20 to 25 percent of women, according to Dr. Sherry Ross, OB/GYN at Providence Saint John’s Health Center.
Galactorrhea’s most common symptom is one or both breasts producing excessive milk. The condition is most common in women, but can also happen to men and newborn babies.
Other symptoms include:
- leaking from nipples that happens at random
- enlargement of breast tissue
- missed or irregular periods
- loss of or lowered sex drive
- abnormal hair growth
- trouble with vision
Galactorrhea has a wide variety of different causes, and in some cases, the cause is hard to pinpoint. Reasons for lactating when not recently pregnant can range from hormone imbalances to medication side effects to other health conditions.
The most common cause of breast milk production is an elevation of a hormone produced in the brain called prolactin. Elevation of prolactin can be caused by:
- underlying medical issues
- a tumor
- overstimulation of the nipples
Other causes include the following.
Some medications may cause galactorrhea. These include:
- birth control
- heart burn medications
- certain pain killers
- blood pressure medicines
- medications that contain hormones
These conditions may also contribute to lactating when not pregnant:
- thyroid issues
- kidney or liver disease
- chronic stress
- tumors or disease of the hypothalamus
- any trauma or damage to breast tissue
- high levels of estrogen (in newborns)
Regular use of certain drugs, like opiates, marijuana, and cocaine, can trigger lactation without pregnancy. It’s important to tell your doctor if you’re using any drugs, and how often. They will need to consider this when diagnosing your galactorrhea.
For some people, having regular breast stimulation may trigger galactorrhea. This can be stimulation during sexual activity, from frequent breast self-exams, or from clothing that rubs against the nipples.
Mothers who are adopting babies and wish to breast-feed can prepare their breasts and increase prolactin levels with pumping.
Treatment for galactorrhea depends on what’s causing it. Your doctor will ask about family history and then may do a few tests to determine the cause. The doctor will also do a physical breast exam. They may try to express some of the discharge for examination in a lab.
Other tests can include:
- bloodwork to see hormone levels
- pregnancy test to rule out pregnancy
- mammogram or ultrasound to check for changes in breast tissue
- MRI to examine the brain for tumors or issues with the pituitary gland
Once your doctor has confirmed a cause, they’ll recommend treatment. Some things can be done on your own, like avoiding tight clothing and reducing the amount of nipple stimulation during sexual activities.
Other treatments need to be supervised by your doctor, like changing medications (for example, switching to a different antidepressant) or taking additional medications to regulate hormones.
Stopping antipsychotic medications, cutting back on marijuana, cocaine, and/or opiates, and limiting nipple stimulation are all ways to stop galactorrhea if these things are found to be the cause, according to Dr. Kevin Audlin of the Institute for Gynecologic Care at Mercy Medical Center in Baltimore. But he points out that it can take a few months for milk production to stop, even after discontinuing medication.
If the cause is a tumor or issues with the pituitary gland, it’s possible you may need surgery. Your doctor will likely do more tests.
Dr. Ross says medication can be given to bring down high prolactin numbers. “Bromocriptine is a medication used to lower the high levels of prolactin in your blood, which helps treat the symptom of lactation.”
Many of the causes of galactorrhea, like hormonal imbalances, tumors, or other medical conditions, are beyond our control. But there are a few things you can do at home to reduce your likelihood of lactating while not pregnant, including:
- avoiding bras or clothing that irritate your nipples
- avoiding stimulating breasts too often
- practicing healthy ways to relieve stress
When to see a doctor
The good news is that galactorrhea typically either goes away on its own or after medical treatment for its underlying cause. But if the discharge coming from your nipples is not milky and looks clear, bloody, or yellow, this is cause for concern. These may be signs of breast cancer. You should see your doctor right away.
Other concerning causes of nipple discharge include:
- a benign (noncancerous) breast growth
- pituitary gland tumors
- a rare form of breast cancer called Paget’s disease of the nipple
If you haven’t been pregnant or nursing in a six-month period and you’re lactating or seeing any other type of discharge from one or both nipples, see your doctor. If something serious is causing the discharge, it’s best to start treatment early.