Prolactin

What is Prolactin?

Prolactin is a hormone produced by the anterior part of the pituitary gland. This gland is a grape sized organ that is found at the bottom of the brain. Prolactin is also known as lactogenic hormone, as it helps women produce milk after childbirth. This hormone is found in both men and women; but, it’s precise role in men is not very well understood: prolactin is supposed to maintain sexual satisfaction and promote sperm production.

When a woman is pregnant, numerous hormones stimulate the breast development and milk production. These hormones include prolactin, estrogen, and progesterone. When the baby is born, the prolactin hormone helps the new you mom initiate and maintain an appropriate breast milk supply for her baby. If the new mom does not breastfeed, her prolactin hormone levels drops down to the pre pregnancy levels. If the new mom starts breastfeeding her baby, the suckling of her baby plays a major role in the continuous prolactin release. The relationship between the suckling and the milk supply becomes like a feedback mechanism where the more the baby drinks milk from his or her mom, the more milk the mom produces; and, the longer the prolactin hormone remains elevated.

Why get tested for Prolactin?

You need to get tested to investigate why a woman who delivered a baby might have unexplained flow of breast milk. This test can also help explain the reasons behind an abnormal nipple discharge, absence of menstrual periods, as well as infertility if women. For men, while prolactin levels are significantly, low, this test can help diagnose the reason behind low sex drive, and erectile dysfunctions. For both genders, such a diagnostic test can help identify a possible pituitary gland tumor, and follow up on the progress of a prolactinoma tumor.

One of the common causes of high prolactin levels is prolactinoma. This condition consists of a tumor development on the pituitary gland that will lead to an over production of prolactin. While it is usually a benign tumor, it may lead to many discomforts. Such tumors are more common in women than men. One of the symptoms of this tumor is the production of milk in non-pregnant or nursing women and even men. When this tumor enlarges, it pressures the optic nerve leading to headaches and vision problems. It can even cause a dysfunction in the production of other hormones of the pituitary gland. In women, such tumors can lead to infertility, loss of libido and sexual function, and even irregularities in menstruations. If prolactinoma is undetected and remains untreated, it could damage its surrounding tissues.

To sum it all, if you have the following symptoms, you need to tested. For women, symptoms include irregular periods or amenorrhea, infertility, breast milk discharge when there is no pregnancy, tenderness in the breast, abnormal acne, pain and discomfort during sex, and menopausal signs such as hot flashes and vaginal dryness. Men’s specific symptoms include a low sex drive, abnormal lack of body and facial hair, difficulties getting erected, breast tenderness and enlargement, testicular dysfunctions; and, very rarely, breast milk production. Other signs that may happen to both men and women include unexplained headaches as well as vision problems.

What can affect the levels of Prolactin?

Some medications can affect your prolactin results, leading to a misdiagnosis and a possible medical error. It is important to note that some medications may alter your results. These include psychiatric drugs, like risperidone and haloperidol, and can boost your prolactin levels. Metoclopramide, used to manage acid reflux and nausea, can raise your prolactin levels. Other medicines that can increase this hormone’s levels include verapamil, reserpine, phenothiazines, opiates medicines, metoclopramide, methyldopa, H2 blockers, estrogens, and butyrophenones.

Marijuana and Cannabis can also peak your prolactin levels. A study, done in collaboration with the Department of Psychiatry in Yale University and VA Connecticut Healthcare system in New Haven, showed that the frequent use of illicit drugs can lead to lower levels of prolactin.

Other factors that can affect your prolactin levels, without being a medical malfunction, are stress, low blood sugar, discomfort, and working out. So, try to pick a day when you are not stressed to give your blood sample. Also, avoid working out before the test.

Food can also have an effect on your prolactin levels, these include red clover, fenugreek and fennel. Before taking the test, avoid eating these three ingredients to make sure your results will be reflective of your physiological health status. Having a recent breast exam, or an intense breast stimulation can have an effect on your normal prolactin levels. Finally, high-protein meals have to be avoided before a test not to lead to false highs.

What do the test results of prolactin mean?

The normal values of this blood test can help diagnose a related condition; and, seek the appropriate treatment. Normal prolactin values in men have to be less than 20 ng/mL. Women, who are not pregnant, have normal values of prolactin set less than 25 ng/mL. Finally, pregnant women’s prolactin hormone levels are normal if they are between 80 and 400 ng/mL. Different laboratories can have slightly different normal value ranges, as they may use different measurements and samples. Also, sometimes, tests that are showing very high levels of prolactin are repeated in the morning, following an 8-hour fast.

High levels of prolactin are normal when the woman is pregnant and post-delivery. If your test results showed numbers that are higher than the normal ranges of this hormone; then, you may have a condition called hyperprolactinemia. This condition is the result of high formation of prolactin. Such elevated levels can be caused by a prolactin-secreting tumor.

Other causes of high prolactin levels include chest wall injury (such as shingles or a tight bra), diseases of the hypothalamus, hypothyroidism, kidney problems, anorexia, drugs, kidney diseases, liver failure, PCOs, and diseases of the pituitary gland. Since high levels of prolactin are common among those with hypothyroidism, testing your thyroid function is recommended. Other tests can also help identify an abnormal level of prolactin, these include testosterone, FSH and LH serum tests.

For those who do not have any symptoms of elevated prolactin levels; but, end up with elevated blood test levels, more tests are needed to rule our macroprolactin. This latter happens when prolactin becomes bound to immunoglobulins, and becomes inactive in the body. According to a study published by the Journal of Reproduction and Infertility, macroprolactin is one of the causes of a misdiagnosed hyperprolactinemia, leading to unnecessary treatments and investigations.

To manage high levels of prolactin, treatment may involve dopamine antagonists such as bromocriptine. Other treatments may involve cabergoline; but, you need to talk to your doctor about whether this is the right treatment for you. Radiotherapy is the solution for those whose body is not responding well to the above-mentioned treatments. If high levels are caused by a tumor, surgery through the nose or upper skull and medications can address the problem and restore your prolactin levels. Other natural methods to lower your levels include changing the diet, managing stress, avoiding intensive workouts, wearing loose clothes, and taking vitamin B6 and E supplements.

If your test results are showing prolactin levels that are lower than normal ranges; then, this is not indicative of any health problem.

Where can I get a prolactin test near me?

Please use our Lab Locator to find find a convenient testing location.

Reviewed By: Dr. Kurt Kloss, MD
Last Reviewed Date: May 27, 2021