Serum Prolactin Level (15-Minute Post-RH Stimulation)
This test measures your prolactin hormone level in your blood after a small dose of recombinant human chorionic gonadotropin (RH). It helps evaluate whether your pituitary gland is functioning normally or if there may be a pituitary tumor or other condition affecting hormone production.
["Assesses pituitary function and potential hormone imbalances after a specific trigger."]
Key facts at a glance
- LOINC
- 44928-0
- Short code
- Prolactin 15M pre TRH IV SerPl-aCnc
- Synonyms
- Prolactin 15M pre TRH IV SerPl-aCnc
- 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 This Test Is Done
Your doctor may order this test if you have symptoms like unexplained infertility, irregular menstrual periods, high or low milk production, headaches, or vision changes that could suggest a pituitary issue. It’s also used in cases where other prolactin tests (like baseline levels) show abnormal results but cause isn’t clear.
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for a few hours before the blood draw. On the day of the test, avoid caffeine or alcohol, as they can affect hormone levels. Let your doctor know about any medications you’re taking, especially those for mental health or thyroid conditions.
What Happens During the Test
A healthcare provider will draw blood from a vein in your arm. You may feel a slight pinch, but it usually takes only a few minutes. The blood sample will be sent to a lab for analysis after your RH dose (if applicable).
What the Results Mean
Results are compared to standard ranges for your age and sex. High prolactin levels may indicate a pituitary tumor, medication side effects, or other conditions like thyroid issues or kidney problems. Low levels might suggest pituitary damage or other hormonal imbalances.
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.
Clinical Significance: Prolactin’s Role and Abnormal Findings
Short name
Prolactin Test (Post-RH Stim)
Frequently asked questions
Why was this test ordered specifically after RH stimulation?
What symptoms might indicate abnormal prolactin levels?
Can medications affect prolactin levels?
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