Prolactin, Serum (Mass Concentration)
This test measures the amount of prolactin, a hormone produced by the pituitary gland, in your blood serum. Prolactin helps regulate breast milk production and affects other body functions, including hormones and reproduction.
["Prolactin levels may help diagnose hormonal imbalances or conditions affecting the pituitary gland."]
Key facts at a glance
- LOINC
- 25736-0
- Short code
- Prolactin sp1 p chal SerPl-mCnc
- Synonyms
- Prolactin sp1 p chal SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 2
- Ref high
- 18
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84146
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Might You Need This Test?
Your healthcare provider may order a serum prolactin test to check for conditions like hyperprolactinemia (high prolactin levels), which can cause infertility, irregular menstrual cycles, or other symptoms. It may also be used to evaluate symptoms such as headaches, vision changes, or unexplained galactorrhea (milk production outside of breastfeeding).
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if instructed by your provider. Wear comfortable clothing and plan to sit or lie down during the blood draw to avoid dizziness. Avoid smoking or drinking alcohol before the test.
What Happens During the Test?
A healthcare professional will insert a small needle into a vein in your arm or hand to collect a blood sample. You may feel a slight pinch, but the process is quick. The blood sample is then sent to a lab for analysis.
What Are Possible Results?
Results are typically reported in nanograms per milliliter (ng/mL) or picograms per milliliter (pg/mL). Your results will be compared to standard reference ranges provided by your healthcare provider to determine if levels are within normal limits or if further evaluation is needed.
Reference range
Adult males: 2-18 ng/mL; Females: 2-29 ng/mLN/A
For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated prolactin levels may indicate conditions such as pituitary tumors, thyroid disorders, kidney problems, or certain medications that affect hormone production. Low prolactin levels can sometimes be linked to pituitary damage, certain medications, or genetic factors. Always discuss your results with your healthcare provider for personalized interpretation.
Short name
Serum Prolactin Level
Frequently asked questions
How long does it take to get my test results?
Can I take anything before or after the blood draw?
What if my prolactin level is outside the normal range?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy