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Serum Prolactin

Also known as PRL test, Prolactin blood test

₹549

You need to provide

Blood

This test is for

Male, Female

Earliest reports in

18 hours

Test Preparation

Overnight fasting is preferred but not mandatory.
Kindly follow your doctor's instructions, if any, on how to prepare for your test.

Understanding Serum Prolactin

What is Serum Prolactin?

The Serum Prolactin test checks the amount of prolactin, a hormone made by the pituitary gland. This hormone plays a role in various body functions. In women, prolactin supports breast growth and milk production during pregnancy and breastfeeding. In men, it helps control immune function and supports reproductive health.

Prolactin plays a crucial role in a wide range of physiological processes, particularly in the initiation and maintenance of breastfeeding in women. Its release is controlled by the pituitary gland and can be influenced by several factors, including pregnancy, breastfeeding, emotional or physical stress, sleep patterns, and certain medications.

The Serum Prolactin test helps diagnose hyperprolactinemia (high prolactin levels).It can be caused by certain medicines, pituitary tumors (called prolactinomas), thyroid problems, and kidney or liver disease. This test can also detect low prolactin levels, which are rare but can be caused by certain drugs or pituitary disorders.

Doctors may recommend this test to women who have unusual breast milk discharge (not related to pregnancy), irregular periods, or fertility problems. On the other hand, men can get this test when they have symptoms like low sex drive, erection problems, or abnormal breast growth.

Prolactin levels change throughout the day and can be affected by stress, exercise, sleep, and sexual activity. Although fasting is not mandatory, your doctor may ask for a morning blood sample, taken 2–3 hours after waking upIf mildly elevated prolactin levels do not match the clinical symptoms, your doctor may recommend a pooled prolactin test on another day. This involves collecting three blood samples at 15–20 minute intervals to reduce the impact of natural fluctuations (pulsatility) in prolactin levels.

Test result ranges may vary slightly across laboratories. Talk with your doctor to understand what your result means. Based on the findings, they may recommend lifestyle changes or medications to manage your health.

What is Serum Prolactin used for?

The Serum Prolactin test is done to:

Check for infertility, irregular periods, or abnormal milk discharge (galactorrhea) in non-pregnant women.
To find out why a woman may not be producing milk after childbirth.
Investigate erection problems or breast discharge in men.
Assess low sex drive in both men and women.
Detect and monitors prolactinomas (non-cancerous tumors) in the pituitary gland.

What does Serum Prolactin measure?

The Serum Prolactin test measures how much prolactin hormone is in the blood. During pregnancy, prolactin works along with estrogen and progesterone to prepare the body for breastfeeding. After delivery, prolactin helps start and maintain milk production. If a woman does not breastfeed, her prolactin levels drop soon after birth.

Besides pregnancy, the most common cause of high prolactin is a prolactinoma. It is a non-cancerous tumor in the pituitary gland. These tumors are more common in women but can also occur in men. If the tumor becomes large, it may press on the optic nerve, causing headaches and vision problems. It can also affect the production of other hormones.

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

Frequently Asked Questions about Serum Prolactin

Q. What is the purpose of the Serum Prolactin test?

This test measures the amount of prolactin hormone in your blood and helps detect prolactin-secreting tumors (prolactinomas).

Q. What are the possible causes for high prolactin levels?

High prolactin can be caused by: 1) Sleep (levels rise during sleep and peak early in the morning) 2) Breastfeeding, breast stimulation 3) Stress, exercise, low blood sugar 4) Hypothyroidism, kidney or liver problems 5) Pituitary tumors, HIV, heart failure, lupus, certain medications (like antipsychotics, dopamine blockers, estrogen pills, and opiates)

Q. What are the possible causes for low prolactin levels?

Low levels can be caused by: 1) Pituitary damage or failure 2) Certain medications like bromocriptine or levodopa 3) Rare hormonal conditions like pseudohypoparathyroidism

Q. Is the Serum Prolactin test safe?

Yes. It involves a simple blood draw. You may feel a small sting or experience minor bruising or swelling, which usually goes away. Applying ice can help reduce swelling.

Q. What is the best time to take this test?

Morning, about 2–3 hours after waking up. Prolactin levels are naturally higher in the evening due to the body’s natural rhythm.

Q. What factors can affect the results of the Serum Prolactin test?

Results can be affected by: 1) Certain psychiatric or hormone medications 2) Stress, poor sleep, alcohol use, or exercise before the test 3) Health issues like hypothyroidism, kidney, or liver disease

Q. What does it mean if prolactin levels are low?

This may indicate to poor pituitary function, a condition called hypopituitarism. In most cases, low prolactin levels do not need treatment.

Q. When can a doctor suggest the Serum Prolactin test in both females and males?

In women: For symptoms like unwanted breast milk, low sex drive, irregular periods, or trouble getting pregnant. In men: For erection issues, low testosterone signs, or abnormal breast development.