Prolactin

Prolactin Blood Test: Your Comprehensive Guide

A prolactin blood test helps doctors find out about sexual problems or low testosterone levels without a clear cause. This applies to both men and women.

Doctors use a blood test to check prolactin levels. This test can help find sexual problems or low testosterone in both men and women. Sometimes, the reasons for these issues are not clear.

Prolactin is a hormone produced in the pituitary gland. It helps women produce milk, but it does other important things, too. Prolactin is involved in how our immune system works and also plays a role in the central nervous system. It helps form a covering on nerves called myelin. Plus, it increases LH receptors on Leydig cells in the testis, which aids in producing testosterone.

What is Prolactin?

Prolactin is a hormone made in the pituitary gland. It helps women produce milk. It also does several other important jobs. Prolactin helps the immune system and helps cover nerves with myelin. It boosts LH receptors found on Leydig cells in the testes, which helps with testosterone production.

Prolactin levels are most high during REM sleep and in the morning. These levels can also increase after exercise, when you eat, during sex, after small surgeries or during seizures.

The pituitary glands in both men and women produce a hormone known as prolactin. In women, prolactin is important for breastfeeding, developing some breast tissue, and helping with milk production. However, high levels of prolactin can seriously affect how men perform sexually. This article will look at how raised prolactin levels impact male sexual performance. It will also explain what the ideal prolactin range is and what the highest levels can be.

Prolactin levels in men usually range from 2 to 18 ng/mL. These normal value ranges can change based on the different laboratories conducting the lab report test. Prolactin levels can also change during the day and can be higher during certain activities like exercise. Nonpregnant women often have higher levels than men. For males, the normal range for prolactin in the blood is still 2 to 18 ng/mL. However, pregnant women may have much higher levels, ranging from 80 to 400 ng/mL.

His doctor may suggest a prolactin blood test if he has signs of high prolactin levels. These signs could be issues like sexual problems. If the man has low sexual desire or finds it hard to get an erection (erectile dysfunction), he may need more tests. These tests can help find out the cause of abnormal nipple discharge and why he has abnormal nipple discharge along with high prolactin levels. Sometimes, treatment is needed to lower these levels, especially if there are large amounts of prolactin, and make sexual function better. This could mean taking medicine that reduces prolactin or having surgery to remove tumors like a prolactinoma. A blood test can also check if a man’s testosterone levels are low or if a prolactinoma is causing high prolactin levels. A prolactin test is usually done when there seems to be a pituitary gland problem, especially if he has low sexual desire or erectile dysfunction. Prolactin levels can be tested when testosterone levels are low.

In conclusion, high prolactin levels can heavily influence how men feel about sex. When prolactin is too high, it can lower testosterone and other hormones that are key for sexual desire and function. Normal prolactin levels can differ by lab, but they usually fall between 2 and 18 ng/mL for men. If a man has signs of high prolactin levels, a doctor might recommend a blood test to check these levels and figure out what could be causing the issue.

Prolactin Blood Test Results: Normal Ranges

During pregnancy and breastfeeding, the level of prolactin in the blood can increase by 10 to 20 times. Strenuous exercise, stress, and not getting enough sleep can also briefly raise prolactin levels, especially during emotional stress. If prolactin levels remain high (more than 30 ng/mL) and a person is not pregnant or breastfeeding, it could mean they have hyperprolactinemia.

Several conditions may cause high prolactin levels. These include:

• Pituitary adenomas
• Diseases of the hypothalamus
• Stimulation of the breast or chest wall
• Kidney disease
• Hypothyroidism

A damaged pituitary gland may not make normal amounts of prolactin, leading to lower levels. Some medications, especially many antidepressants, can also raise the level of prolactin too high. Hyperprolactinemia can cause problems like galactorrhea, missed periods, and infertility in women. In men, it can result in impotence and low testosterone. Kidney disease, hypothyroidism, renal failure, and prolactin-secreting pituitary adenomas are common reasons for having high prolactin levels.

Adult Males | 2.0-18.0 ng/mL

Adult Females

Non-Pregnant | 3.0-30.0 ng/mL

Pregnant | 10.0-209.0 ng/mL

Postmenopausal | 2.0-20.0 ng/mL

Prolactin’s Role in Lactation and Breastfeeding

Prolactin is a hormone that plays a key role in milk production and breastfeeding, stimulating breast development. It helps the mammary glands in the breasts to produce milk. A woman's level of the hormone prolactin rises a lot during pregnancy, making it especially important for pregnant people. This change readies her body for breastfeeding. After she gives birth, breastfeeding keeps the levels of prolactin high. This aids in making milk and maintains a good milk supply. A blood test for prolactin may be suggested for those who struggle with breastfeeding. Low levels of prolactin can impact milk production.

Causes of High Prolactin

Hyperprolactinemia means having high prolactin levels in men. This can occur because of various health problems, medications, and changes in the body. Here are the main reasons:

Medical Conditions

• A prolactinoma is the main cause of high prolactin levels.
• It is a harmless tumor found in the pituitary gland.
• This tumor produces excess prolactin.

Hypothyroidism is when the thyroid gland does not function properly. When this happens, it can lead to high levels of prolactin. This occurs because the body makes more thyrotropin-releasing hormone (TRH). The extra TRH then causes the body to release more prolactin.

Chronic kidney disease can make it tough for the body to get rid of prolactin in the blood. This can lead to higher levels of prolactin.

Liver Disease: Liver failure can affect prolactin levels. This change happens because the liver struggles to break down and get rid of the hormone.

• Tumors near the pituitary gland can change how dopamine works.
• Dopamine usually helps to prevent the release of prolactin.

Medications

• Dopamine antagonists are drugs that stop dopamine from acting on its receptors.
• These drugs include antipsychotics.
• They can increase prolactin levels in the body.
• This occurs because dopamine usually helps handle prolactin release.
• Antidepressants: Certain antidepressants, like tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs), can increase prolactin levels.
• Some blood pressure medications can change levels of prolactin.
• Opioids are pain relievers that can increase prolactin levels.

Physiological States and Other Factors

• Stress: Both physical stress and emotional stress can quickly increase prolactin levels.
• Intense exercise can lead to temporary increases in prolactin levels.
• Having sex can cause an increase in prolactin levels.
• A chest injury or irritation can occur.
• Issues like shingles can lead to this.
• Tight clothes can also make more prolactin get released.

High Prolactin Consequences

Women are more likely than men to have high prolactin levels. This is called hyperprolactinemia. However, several factors can impact both men and women. These factors include pituitary tumors, certain prescription drugs, and some medications for high blood pressure.

Men with high levels of prolactin may face several sexual problems. These problems can include decreased sperm production, erectile dysfunction, and a low sex drive. Additionally, liver disease, like cirrhosis, can also raise levels of prolactin in both men and women.

High levels of prolactin are a significant problem that result in low testosterone production. Testosterone is very important for men’s sexual desire and ability to perform. When prolactin levels are very high, it can stop the production of testosterone. This leads to lower sexual desire. It also affects how well a man can maintain an erection. In men, high levels of prolactin can cause reduced sex drive and erectile dysfunction (ED). This condition is also known as impotence. It means a man can't get or keep an erection.

High prolactin levels can cause problems with other hormones that are important for sexual health. They can lower testosterone production as well. For instance, too much prolactin can block the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormones are essential for keeping testosterone levels stable and ensuring good sperm health in men.

High prolactin levels can reduce testosterone. This can cause issues with sexual function.

Higher levels of prolactin are connected to tumors found in the lungs, pituitary gland, and kidneys. Doctors might look at prolactin levels to help find out more about sexual problems in both men and women when there is no clear reason for them.

Drugs, supplements, and health issues like pituitary adenomas can affect the levels of prolactin in the blood. Some factors that can change these levels include hypothyroidism, antiepileptic drugs, antidepressants, estrogen, opiates, diuretics, certain growth hormone-releasing peptides, and arginine.

Hyperprolactinemia occurs when levels of prolactin are higher than 50 ng/dL. This condition is mainly due to tumors in the anterior pituitary gland called prolactinomas. High levels of prolactin are more common than low levels. Prolactinomas can change how the hypothalamus and pituitary gland work together. When prolactin levels are high, they can reduce the release of GnRH. GnRH is important because it helps the pituitary gland produce Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH). A drop in these hormones can lead to low testosterone and reduced sperm production. In men, this can result in problems like impotence. A sign of prolactinomas in men is unusual lactation. This means their breast tissue can make small amounts of milk when their prolactin levels are high.

Modest levels of prolactin elevation, which are between 25 and 50 ng/mL, can be linked to several health problems. Conditions like primary hypothyroidism and kidney disease often cause these higher levels of prolactin. This occurs because the body processes or gets rid of prolactin differently. Before assuming a tumor is the cause of the increased prolactin, it’s important to check for all other possible reasons.

Some medicines can increase the amount of prolactin in men's blood. You can find more information in the table. (From Ther Clin Risk Manag. 2007 Oct; 3(5): 929–951.)

What Are Prolactinomas?

Prolactinomas are tumors that can be either small or large. They are called microadenomas when they are less than 10 mm and macroadenomas when they are over 10 mm. A very high prolactin level, which is more than 50 ng/mL, usually indicates there is a pituitary tumor present. Bigger tumors generally cause higher levels of prolactin. Research shows that a pituitary tumor larger than 10 mm is often connected to a significant rise in prolactin levels in the blood. This indicates it is likely a macroprolactinoma. However, sometimes a normal or low prolactin level can occur. To check for the presence of a prolactinoma, an imaging test like an MRI test is needed.

Other Pituitary Gland Tumors Can Cause High Prolactin

Other kinds of tumors in the pituitary gland can release thyroid-stimulating hormone or growth hormone. This can cause high levels of prolactin. If your prolactin levels are high, your doctor may recommend more tests. These tests will help determine the cause and the best treatment for you.

Low Prolactin Consequences:

Low prolactin levels in the blood can lead to sexual problems and other health issues. Prolactin helps with the immune system and keeps the heart muscle strong. This is why it is important to have healthy prolactin levels.

When Should Men Get a Prolactin Blood Test?

Men who are not getting testosterone replacement therapy (TRT) and have low testosterone levels (T level <150 ng/dL) should be tested for low levels of LH. If these men have low LH, a prolactin test should be done to see if there is a problem with the pituitary gland. If a problem is thought to be present, these men will undergo an MRI.

• Some men can have liquid coming from their nipples.
• This has occurred in a few men who are using anabolic steroids.

Men who take testosterone replacement therapy (TRT) may still have problems with erectile dysfunction after 8 to 12 weeks of treatment. This is true even if their testosterone levels are above 500 ng/dL and free testosterone is more than 2 percent of total testosterone. Prolactin testing is not done often in initial lab tests. This is because it can be costly, and only about 5 percent of men have high prolactin levels. So, many feel it is not worth the expense. However, if a man's total testosterone is very low or if TRT does not improve erectile dysfunction, then checking prolactin levels might be a good idea.

Common Questions About the Prolactin Blood Test:

Can prolactin levels fluctuate over time, and if so, how often should someone have this test done?

Prolactin levels can vary with time. Factors like stress, some medications, pregnancy, breastfeeding, and exercise can cause short-term changes in these levels. If your doctor asks you to track your prolactin levels, they will specify how often to check them based on your needs. Sometimes, you need to monitor them regularly. This helps to see how prolactin levels change or to find out if treatment for problems related to abnormal prolactin levels is working. It’s important to follow your doctor’s instructions and discuss any worries or questions you have about prolactin testing.

Is there any special diet or fasting required before the prolactin blood test?

It depends on which test you are talking about. Some medical tests need you to fast, while others do not. Fasting is often important for getting accurate results. Certain foods and drinks can change the results. It is wise to talk to your doctor or the place where you will take the test. They can let you know if there are specific rules for eating or if you need to fast. They will give you the correct instructions to prepare for the test.

What are some reasons why a doctor might order a prolactin blood test?

There are several reasons why a doctor may want you to take a prolactin blood test. This test checks how much prolactin is in your blood. The pituitary gland, a tiny gland at the base of the brain, produces prolactin, a hormone that is crucial for milk production in breastfeeding women. Yet, symptoms of high prolactin levels can signal other health conditions. Some common reasons for this blood test include:

• High levels of prolactin can impact ovulation.
• They can also throw off menstrual cycles.
• This disruption may lead to fertility issues.
• Problems with prolactin can cause women to have irregular or no periods.
• It is important to check these menstrual issues.

The pituitary gland helps produce and control prolactin. If there are issues or tumors in the pituitary gland, it can lead to the production of too much prolactin.

Galactorrhea happens when a person produces breast milk, even if they are not pregnant or nursing. This can occur due to high levels of prolactin in the body.

Monitoring how well the treatment is working is very important. If someone has hyperprolactinemia, their levels of prolactin are too high. They may need regular tests to check if the treatment is effective. These tests also help see if their levels are back to a normal range.

A blood test for prolactin alone won't provide a clear diagnosis. But it can suggest the need for additional tests and treatments if necessary. It is important to discuss this with your healthcare provider.

Citations:

[1] What Causes High Prolactin Levels in Men?

[2] Hyperprolactinaemia: Physiological Aspects

[3] Hyperprolactinemia: Clinical Manifestations and Evaluation

[4] Prolactinoma: Diagnosis and Treatment

[5] Prolactin Test

[6] Prolactin: Man’s Friend or Foe?

[7] Hyperprolactinemia and Implications for Women's Health

[8] Galactorrhea: Symptoms and Causes

[9] What Are the Side Effects of High Prolactin Levels?

[10] Diagnosis and Management of Hyperprolactinemia

[11] Hyperprolactinaemia

[12] Pituitary Tumors: Symptoms and Causes

[13] Hyperprolactinemia: Causes, Symptoms, and Treatment

[14] Hyperprolactinemia and Prolactinomas

[15] Galactorrhea: Diagnosis and Treatment

[16] Hyperprolactinemia (Prolactin Levels)

[17] Hyperprolactinemia: Symptoms, Causes, and Treatment

[18] Prolactin Levels Test

[19] High Prolactin Levels and Prolactinomas: Beyond the Basics

[20] Prolactinoma: Symptoms and Causes