Prolactin Test (PRL)

• In non-pregnant women prolactin test is done to investigate women with  menstrual irregularities, infertility and menopausal symptoms. 
• In lactating mothers test is also done to investigate cause of abnormal breast milk discharge
• In men its is done to evaluate for Lowsex drive , testicular failure or abnormal discharge from breast 
• Test is also done to diagnose suspected pituitary tumours, with symptoms of changes in vision and headache

Prolactin test requires a blood sample. A tourniquet (elastic) band is placed tightly on the upper arm. The patient is then asked to make a fist. This helps in the build-up of blood filling the veins. The skin is disinfected before needle insertion and the blood sample is collected in vacutainer.

• High Levels of Prolactin are seen in - Prolactinoma, Polycystic Ovarian Disease, hypothyroidism, liver disease, and hypogonadism. Macroprolactinemia must be ruled out.
• MIld prolactin excess (26.5 to 50 ng/ml) is seen with exercise, lactation, emotional stress, and exercise. It may be of no clinical relevance. In such cases, it's advised to repeat the test after 1 month.
• Levels between 51-75 ng/ml are associated with menstrual disorders and subclinical hypothyroidism.
• Levels above 100 ng/ml are associated with hypogonadism, amenorrhea, galactorrhoea 
• Low levels of Prolactin are seen in - Pituitary deficiency and in cases of Pseudohypoparathyroidism

The normal range of prolactin in the blood is:

• Males: 2 – 18 nanograms per millilitre (ng/ml)
• Non-pregnant females: 2 – 29 ng/ml
• Pregnant females: 10 – 209 ng/ml

A normal level of prolactin is required for reproductive health. It is also needed to function normally. Abnormal levels require attention. Conscious lifestyle changes and medical intervention is required if the levels are abnormal.

A higher-than-normal level of prolactin in the blood could be due to:

• Stress while giving the test
• Certain drugs or food items
• Prolactinoma. It is a benign tumour in the pituitary gland
• Hypothalamus-associated diseases
• Anorexia or a type of eating disorder
• Drugs prescribed to treat depression, high blood pressure and psychosis
• Chest injury or irritation due to scars, tight innerwear, shingles, etc.

A lower-than-normal level of prolactin in the blood could be due to:

• Hypopituitarism. This means impairment in the pituitary gland’s ability to produce prolactin
• Certain drugs like dopamine, levodopa, ergot alkaloid derivatives etc.

Sometimes, when you are asked to take a prolactin test, it could mean that your doctor suspects an abnormality. However, not every time your levels are off range does it mean that you have an underlying disorder. If your doctor suspects prolactinoma, then you may be asked to do an MRI or a CT. Upon confirmation, you will be administered medicines to treat it.

A high prolactin level can be one of the causes of irregular menstruation. However, it does not always mean that a high prolactin level is the only cause of irregular menstruation. Your doctor may ask you to take other tests to assess your overall health. He will then narrow down the root cause of irregular menstruation.

If you are a woman, you may be asked to undergo a prolactin test if you:

• Experience menstrual irregularities
• Experience amenorrhea
• Experience unexplained subfertility (trying to get pregnant but not successful for at least six months to one year)
• Have painful intercourse
• Have acne and excess hair growth on your face and body
• Have unusual breast discharge
• Have sudden vision impairment
• Have less libido
• Have hypothyroidism

If you are a man, you may be asked to undergo a prolactin test if you have:

• Erectile dysfunction
• Less libido
• Unusual growth and/or discharge from your chest
• Lesser body and/or facial hair
• Smaller muscles
• Apart from these, you may also be suggested to undergo a prolactin test if you have:
• Sudden blurred vision
• Weak bones
• Reduction of other hormones

PRL test