FSH (Follicle Stimulating Hormone) in Serum/Plasma, Immunoassay
This test measures your levels of follicle-stimulating hormone (FSH), a hormone produced by the pituitary gland that plays a key role in reproductive health.
["FSH helps regulate egg development in women and sperm production in men."]
Key facts at a glance
- LOINC
- 25644-6
- Short code
- FSH sp2 p chal SerPl IRP2-aCnc
- Synonyms
- FSH sp2 p chal SerPl IRP2-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 12.5
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- nd-irp
- CPT
- 83001
- 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 Might Be Ordered
Your doctor may recommend this test to evaluate fertility issues, assess hormone imbalances, diagnose conditions like premature ovarian insufficiency (POI) in women, or check for pituitary gland problems. It can also help monitor hormone therapy or track progress in conditions affecting reproductive function.
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 blood is drawn early in the morning. Avoid strenuous activity or caffeine for a few hours beforehand. If you’re taking medications that affect hormones, let your doctor know.
What Happens During the Test
A healthcare professional will draw blood from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause discomfort. The blood sample is sent to a lab for analysis using an immunoassay method to measure FSH levels accurately.
What the Results Mean
Results are interpreted based on your age, sex, and medical history. High or low FSH levels can signal underlying health concerns, but your doctor will discuss findings with you in the context of your overall health.
Reference range
Follicular: 3.5-12.5 mIU/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 FSH levels may indicate early menopause, ovarian dysfunction, or conditions like polycystic ovary syndrome (PCOS). Low FSH levels can suggest pituitary disorders or hypogonadism. Your doctor will use these results alongside other tests and symptoms to guide diagnosis and treatment plans.
Short name
FSH Level
Frequently asked questions
How long does it take to get my FSH test results?
Can lifestyle changes affect my FSH levels?
Is fasting required for this test?
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