What is this test?
Prolactin is a hormone of the pituitary gland, mainly related to the formation of breast milk, but it also affects reproductive function.
Why might it be ordered?
- When releasing breast milk outside of the breastfeeding period, irregular cycle or difficulty in getting pregnant.
- For symptoms that warrant pituitary assessment or to monitor treatment.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Stress, physical exertion, and breast stimulation can temporarily increase prolactin. Follow the guidelines for time and a short break before the test. Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
If the result is abnormal, a repeat sample after a period of quiet rest or a macroprolactin test may be needed. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.