Prolactin Disorders: Understanding Galactorrhea, Infertility, and Effective Treatments

When your breasts start leaking milk and you’re not pregnant or nursing, it’s not just confusing-it’s scary. You might panic, thinking it’s cancer. Or you might feel embarrassed to even mention it to your doctor. But here’s the truth: galactorrhea is more common than you think. About 1 in 5 women will experience it at some point in their lives, and it’s rarely a sign of something dangerous. The real issue isn’t the milk-it’s what’s causing it. High levels of prolactin, a hormone made in the pituitary gland, are usually behind the scenes. And when prolactin runs wild, it doesn’t just make milk-it can stop your periods, mess with your fertility, and leave you wondering what’s going on in your body.

What Exactly Is Galactorrhea?

Galactorrhea is milky nipple discharge that happens outside of pregnancy or breastfeeding. It’s not a disease. It’s a symptom. And it’s often tied to something deeper: hyperprolactinemia, which means your prolactin levels are too high. Normal levels for non-pregnant women are between 2.8 and 29.2 ng/mL. Once you cross 25 ng/mL, doctors start looking for causes. In about 70-80% of cases, the discharge comes from both breasts. If it’s only one side, that raises a red flag-but even then, it’s not always cancer. Breast cancer usually causes bloody or clear, sticky fluid, not milky. Galactorrhea’s milk is thin, white, and often comes out when you squeeze your breast-or sometimes just by itself.

Why Does This Happen? The Top Causes

Prolactin is normally kept in check by dopamine, a brain chemical that tells your pituitary gland to slow down. When that system breaks, prolactin rises. Here are the most common reasons:

• Prolactinoma: A benign tumor in the pituitary gland that makes too much prolactin. These are the #1 cause. Microprolactinomas (under 10 mm) are common and often don’t cause headaches or vision problems.
• Medications: Antidepressants like SSRIs (sertraline, fluoxetine), antipsychotics, some blood pressure drugs, and even certain herbs like fenugreek can spike prolactin.
• Thyroid problems: Low thyroid function (hypothyroidism) can trigger prolactin overproduction. That’s why doctors always check TSH levels.
• Stress or physical irritation: A hard chest exam, tight bras, or even intense exercise can temporarily raise prolactin. That’s why blood tests need to be done calmly, after resting for 20-30 minutes.
• Idiopathic: In about 1 in 3 cases, no cause is ever found. That doesn’t mean it’s not real-it just means science hasn’t figured out why yet.

How Galactorrhea Leads to Infertility

High prolactin doesn’t just make milk-it shuts down your reproductive system. Prolactin suppresses GnRH, the hormone that tells your ovaries to release eggs. No GnRH? No ovulation. No ovulation? No periods. That’s why many women with galactorrhea stop getting their periods altogether-this is called amenorrhea.

The link is strong: 80-90% of women with hyperprolactinemia and missed periods will start ovulating again once prolactin levels are brought back to normal. That’s not magic. That’s science. Dopamine agonists like cabergoline don’t just stop the milk-they restore fertility. One woman on Reddit shared: “After 18 months without a period, I started cabergoline. My period came back in 3 months. I got pregnant naturally 4 months later.” That’s the kind of outcome doctors see regularly.

How It’s Diagnosed: No Guessing, Just Testing

You won’t get a diagnosis from a look or a feeling. You need tests.

1. Blood tests: Prolactin, TSH (thyroid), and sometimes kidney function (because kidney disease can raise prolactin).
2. Repeat prolactin test: Stress, sleep deprivation, or even a rough blood draw can spike levels by 10-20 ng/mL. If your first test is borderline, they’ll repeat it after you’ve rested.
3. MRI scan: If prolactin is over 100 ng/mL, an MRI of the brain is almost always done to check for a pituitary tumor. Even if you feel fine, a tumor that size can grow slowly and cause problems later.
4. Breast exam: Your doctor will check for lumps, nipple changes, or discharge that looks bloody or clear-those need further imaging.

If the discharge is unclear, a cytology test (looking at the fluid under a microscope) might be done. It’s not common, but it helps rule out cancer when there’s doubt.

Treatment: What Works, What Doesn’t

The goal isn’t to stop the milk-it’s to fix the cause. And for most people, that means dopamine agonists.

Cabergoline (Dostinex)

This is the gold standard. It’s taken twice a week, usually starting at 0.25 mg. Most people see prolactin levels drop within weeks. Milk stops in 2-8 weeks. Periods return in 1-3 months. Fertility often rebounds quickly. Studies show 83% of patients normalize prolactin within 3 months. Side effects? Mild nausea or dizziness in 10-15% of people. Rarely, high doses over a year can affect heart valves-but that’s not a concern at standard doses.

Bromocriptine

Older, cheaper, but harder to tolerate. Taken daily, it causes nausea in 25-30% of users. Many people have to take it at bedtime just to sleep through the sickness. It’s still effective-76% normalize prolactin-but the side effects make people quit more often.

Other Options

• Switching medications: If an antidepressant is the culprit, switching from sertraline to bupropion often fixes both mood and prolactin. One patient wrote: “My discharge stopped within two weeks of switching.”
• Thyroid treatment: If low thyroid is the cause, levothyroxine fixes both the TSH and the prolactin.
• Surgery: Only for large tumors (macroadenomas) that don’t shrink with meds or are pressing on nerves. Most prolactinomas respond so well to drugs that surgery is rare.

What About Idiopathic Galactorrhea?

If no cause is found, you’re not alone. About 35% of cases fall into this group. The good news? About 30% of these people get better on their own within a year. No treatment needed. Just watchful waiting. But if you’re trying to get pregnant or the discharge is bothering you, treatment with cabergoline still works-even without a clear cause. The body responds to the drug, not the diagnosis.

What’s New in 2026?

The field is evolving. In January 2025, the FDA approved a new extended-release form of cabergoline that you only take once a week. Early results show 89% effectiveness-slightly better than the old version. Novartis is testing a new drug that blocks prolactin receptors directly, not by boosting dopamine. If it works, it could help people who can’t tolerate dopamine agonists. And clinics are starting to team up endocrinologists with breast specialists to cut diagnosis time from 8 weeks down to 3.5.

What to Expect Long-Term

Most people stay on medication for 6-12 months. Once prolactin is normal and you’re ovulating, your doctor might slowly reduce the dose. Some people can stop entirely. Others need to stay on a low dose long-term, especially if they had a tumor. Regular blood tests every 6 months keep things on track.

The big win? Fertility. If you’ve been trying to get pregnant and nothing’s worked, high prolactin could be the hidden culprit. Fix that, and your chances jump dramatically. One study found 78% of women treated for hyperprolactinemia conceived within a year-without IVF.

When to Worry

Not every discharge needs treatment. But if you notice:

• Bloody, clear, or sticky fluid
• One-sided discharge with a lump
• Headaches, vision changes, or unexplained weight gain
• Periods stopped for more than 3 months

…see a doctor. Don’t wait. These aren’t typical galactorrhea signs. They need faster action.

Final Thoughts

Galactorrhea isn’t embarrassing. It’s a signal. Your body is telling you something’s off-and it’s usually fixable. You don’t need to suffer through nausea from bromocriptine. You don’t need to live with missed periods or infertility if it’s just a hormone imbalance. Cabergoline works. It’s safe. And it brings back your body’s natural rhythm. The most important step? Getting tested. Don’t ignore it. Don’t assume it’s stress. Get your prolactin checked. Your future self-your fertility, your peace of mind-will thank you.