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Serum Prolactin

Also known as PRL test, Prolactin blood test

₹414~~₹538~~ 23% Off

You need to provide

Blood

This test is for

Male, Female

Test Preparation

Overnight fasting is preferred.

Understanding Serum Prolactin

What is Serum Prolactin?

A Serum Prolactin test measures the level of prolactin, a hormone essential for breast development and the production of breast milk in lactating women. It may be done if you experience symptoms of high or low prolactin levels or your doctor suspects prolactinoma, a tumor in the pituitary gland.

Prolactin is a hormone produced by the pituitary gland that impacts various bodily functions. Abnormal levels of prolactin in the blood can alter the release of other hormones which may lead to several health concerns in both men and women. Its elevated levels can also interfere with the functioning of the ovaries and testes.

Your doctor may advise a Serum Prolactin test if you show symptoms like infertility, changes in sexual drive, breast milk production that is not associated with pregnancy or childbirth, or irregular periods. This test may also be suggested to men if they show symptoms of high prolactin, like low testosterone levels, erectile dysfunction, and abnormal breast enlargement. This test also helps to monitor the health conditions associated with abnormal levels of this hormone.

Usually, overnight fasting is preferred for this test. Therefore, do not eat or drink anything except water before the test. Prolactin is secreted episodically, so a multiple-sampling technique, i.e., pooling equal volume of sera from specimens drawn at 20-30 mins intervals, is advantageous.

Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The results will help the doctor determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, decide whether or not medication will be required to manage your condition, and formulate your overall treatment plan.

What is Serum Prolactin used for?

A Serum Prolactin test is done:

When a person has any signs and symptoms of prolactinoma, such as unexplained headaches, visual impairment, and unexplained discharge from nipples.
When a woman is experiencing infertility or irregular menstrual periods.
When a man has symptoms such as decreased sex drive (libido), nipple discharge, infertility, or low testosterone levels.
To evaluate the role of prolactin in case of lactation failure in women after childbirth.
To determine the cause of breast milk production which is not associated with pregnancy.
To monitor the treatment of prolactinoma (tumor of the pituitary gland that causes high levels of prolactin) in both men and women and detect its recurrence.
To evaluate the functioning of the pituitary gland.

What does Serum Prolactin measure?

A Serum Prolactin test measures the levels of prolactin hormone in a person’s body. During pregnancy, prolactin, estrogen, and progesterone hormones stimulate breast milk development. Following childbirth, prolactin helps initiate and maintain the breast milk supply. If a woman does not breastfeed, her prolactin concentration will soon drop back to pre-pregnancy levels.

Besides pregnancy, the most common cause of elevated prolactin concentration is prolactinoma, a prolactin-producing tumor of the pituitary gland. Prolactinomas are the most common type of pituitary tumor and are usually benign (non-cancerous). They develop more frequently in women but are also found in men.

If the pituitary gland and/or the tumor enlarge significantly, it can put pressure on the optic nerve, causing headaches and visual disturbances, and can interfere with the other hormones that the pituitary gland produces.

Interpreting Serum Prolactin results

Interpretations

High levels of prolactin can be seen in:

Tumors of the pituitary gland that produces and releases prolactin (Prolactinoma)
Diseases of the hypothalamus (a gland located in the brain)
Kidney disease
Liver disease
Hypothyroidism
Polycystic ovary disease (PCOD)
Conditions like anorexia nervosa (eating disorder)

Low levels of prolactin can be seen in:

Pseudohypoparathyroidism
Patients taking bromocriptine
Pituitary deficiency like necrosis or infarction of the pituitary gland

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Serum Prolactin

Frequently Asked Questions about Serum Prolactin

Q. What are some of the causes of increased prolactin levels?

Some common causes of increased prolactin levels are sleep (levels rise rapidly during sleep and peak in early hours), nursing, breast stimulation, exercise, hypoglycemia, emotional stress, exercise, ambulation, protein ingestion, hypothyroidism, pituitary tumors (prolactinomas and others), hypothalamic/pituitary stalk lesions, renal failure, HIV infection (21%), CHF, SLE, advanced multiple myeloma, Rathke cleft cyst, and intake of drugs like dopamine antagonists (phenothiazines, haloperidol, risperidone, reserpine, methyldopa, estrogens, opiates, cimetidine).

Q. What are some of the causes of decreased prolactin levels?

Some of the causes of decreased prolactin levels are pituitary necrosis/infarction, use of some drugs like bromocriptine, levodopa, etc., and conditions like pseudohypoparathyroidism.

Q. Is there any risk associated with a Serum Prolactin test?

There is usually no risk associated with this test. However, some people may feel a slight sting when a needle is pricked to collect a blood sample and may experience some bleeding that is normal and usually not bothersome. Rarely, some people may also experience slight swelling or bruising at the site of the needle prick. Applying ice 3-4 times a day for about a week may help reduce swelling and bruising. If it does not get better, consult your doctor.

Q. What happens if the test results show a low prolactin level?

If your prolactin levels are below the normal range, this could mean your pituitary gland is not functioning properly. This is known as hypopituitarism. Lower levels of prolactin usually do not need any medical treatment.

Q. What are the symptoms of prolactinoma in both men and women?

The symptoms of prolactinoma that are seen in both men and women include reduced bone density, loss of interest in sexual activity, headaches, visual disturbances, and infertility.

Q. I got my prolactin levels tested. Now, my doctor has advised me for a thyroid test. Why is it so?

In many patients, high levels of prolactin may be seen due to low levels of thyroid hormones (hypothyroidism). Therefore, you may be asked to get your thyroid tests done. However, high levels of prolactin do not cause low levels of thyroid hormones.

Q. Do I need additional tests along with Serum Prolactin?

Your doctor may advise additional tests depending on your situation. If your prolactin levels are high, an imaging test called a magnetic resonance imaging test (MRI) may be advised to rule out a prolactinoma. Also in women, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) tests may be performed to help evaluate ovulation and fertility issues. A few other tests such as thyroid-stimulating hormone (TSH), blood urea nitrogen (BUN), creatinine, and electrolytes may also be ordered to check thyroid and kidney functions. An eye examination may also be performed to evaluate visual disturbances.

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