Sarah sat in my clinic, a little anxious. “Doc,” she began, “my periods have been all over the place, and well… this is a bit embarrassing, but I’ve noticed some milky stuff from my nipples. I’m definitely not pregnant.” She looked down, clearly worried. It’s a scenario I’ve encountered more than a few times, and often, our conversation eventually lands on a tiny but mighty hormone called prolactin.
So, what exactly is prolactin? Think of it as a special messenger in your body, a hormone primarily known for its role in milk production – that’s why it’s also sometimes called lactotropin. But it’s not just about breastfeeding; this hormone is involved in hundreds of different bodily processes. It’s mainly made in a small gland at the base of your brain called the pituitary gland.
What Does Prolactin Do, Really?
Okay, so we know prolactin is a busy bee. Its two headliner jobs are:
- Getting the mammary glands (the milk-making factories in the breasts) ready.
- Helping with lactation, which is the fancy term for making and releasing breast milk.
During pregnancy, prolactin teams up with other hormones like estrogen and progesterone. Together, they work on developing breast tissue, specifically these little pockets called mammary alveoli where milk is made and stored. It’s quite the construction project!
Then, after a baby arrives, something interesting happens. The cells in those mammary alveoli become even more receptive to prolactin. This allows milk to flow. It’s one of those fascinating ‘positive feedback loops’ in our bodies – when a baby suckles, it actually signals the pituitary gland to release more prolactin, which means more milk. Clever, isn’t it?
The Source of Prolactin
As I mentioned, most of your prolactin comes from your pituitary gland. It’s a real command center for hormones. The production and release of prolactin are carefully managed by other body chemicals, mainly dopamine (a type of neurotransmitter, or brain chemical messenger) and estrogen (another key hormone).
When Prolactin Levels Go Off-Kilter
It’s perfectly normal for prolactin levels to go up when you’re pregnant or breastfeeding. That’s its job! But sometimes, levels can also rise temporarily for other reasons. Nothing to usually worry about, but things like:
- Physical stress, like if you’re in pain
- A good workout
- After eating a meal
- Sexual intercourse
- Nipple stimulation (even if not breastfeeding)
- An injury to your chest area
- Sometimes after a seizure
Now, if prolactin levels stay high for a long time when they shouldn’t, we call this hyperprolactinemia. This needs a closer look.
High Prolactin (Hyperprolactinemia): What to Watch For
The most common reason for persistently high prolactin is something called a prolactinoma. Now, that word – prolactinoma – sounds a bit intimidating, I know. But it’s usually a benign (that means non-cancerous) tumor on the pituitary gland that just happens to make extra prolactin. Think of it like a tiny factory working overtime when it shouldn’t be.
When prolactin is too high, it can cause some noticeable symptoms. You might experience:
- Trouble getting pregnant (infertility)
- A dip in your sex drive
- A milky discharge from your nipples, even if you’re not pregnant or breastfeeding (we call this galactorrhea)
- Irregular periods or no periods at all
- For men, difficulty with erections (erectile dysfunction)
What About Low Prolactin?
Honestly, we don’t often see problems with prolactin being too low, unless, of course, you’ve just had a baby and are expecting to produce milk. If you’re not pregnant or breastfeeding, your prolactin levels are naturally low, and that’s normal.
The main time low prolactin becomes an issue is if a new mother isn’t producing breast milk. In some rare cases, a condition called hypopituitarism might be the culprit. This is when the pituitary gland isn’t making enough of one or more hormones. But, it’s important to remember that making milk is complex, and there can be many reasons for a low milk supply. It’s not always about prolactin alone.
Checking Your Prolactin: The Blood Test
If you come to me with symptoms like Sarah’s, or other signs that suggest your prolactin might be off, one of the first things we’ll likely do is a simple prolactin (PRL) blood test. It’s a straightforward way to see what your levels are doing. This test can also give us clues about how well your pituitary gland is functioning.
What are “Normal” Prolactin Levels?
Good question! What’s ‘normal’ can vary a bit. Generally, we look for these ranges:
- For men: Usually less than 20 ng/mL (nanograms per milliliter).
- For women who aren’t pregnant or breastfeeding: Typically less than 25 ng/mL.
- For those who are pregnant or breastfeeding: Levels can jump up quite a bit, often between 80 to 400 ng/mL.
It’s always a good idea to look at the specific reference range on your lab report, as different labs might have slightly different numbers. And, of course, we’ll go over your results together.
When Should You Chat With Your Doctor?
If you’re experiencing any of the symptoms we talked about – especially things like unexpected milky discharge, changes in your periods, fertility concerns, or a drop in libido – it’s a good idea to make an appointment. We can figure out if a prolactin test is needed.
And if you’re a new mom struggling with milk supply, please don’t suffer in silence. Reach out. Sometimes a lactation consultant or a doctor specializing in breastfeeding medicine can be incredibly helpful. We’re here to support you.
Key Things to Remember About Prolactin
Let’s quickly recap the main points about prolactin:
- Prolactin is a hormone mainly from your pituitary gland, crucial for milk production and breast development.
- Levels naturally rise during pregnancy and breastfeeding.
- High prolactin (hyperprolactinemia) can be caused by pituitary tumors (prolactinomas), medications, or stress, leading to symptoms like galactorrhea, irregular periods, and infertility.
- Low prolactin is mainly a concern for new mothers if it affects milk supply.
- A simple blood test can measure your prolactin levels.
Hormones can seem complicated, I know. But understanding even a little bit about them, like with prolactin, can empower you to take charge of your health. You’re never alone in figuring these things out.