Follicle Stimulating Hormone (FSH) in Serum/Plasma
This test measures the amount of follicle-stimulating hormone (FSH) in your blood. FSH is a hormone produced by the pituitary gland that plays a key role in reproductive health, including egg and sperm development.
["FSH helps regulate fertility and hormone balance in both men and women."]
Key facts at a glance
- LOINC
- 25641-2
- Short code
- FSH 1h p 100 ug LRH IV SerPl-aCnc
- Synonyms
- FSH 1h p 100 ug LRH IV SerPl-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
- 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 Might This Test Be Done?
Your healthcare provider may order this test to check for hormonal imbalances, evaluate fertility issues, diagnose conditions like polycystic ovary syndrome (PCOS), or monitor treatment for hormone-related disorders. It may also be used to assess conditions affecting the pituitary gland or ovaries/testes.
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 blood draw if your lab requires it. Avoid strenuous activity or smoking for a few hours beforehand. If you’re taking medications that affect hormones, let your provider know.
What Happens During the Test?
A healthcare professional will collect a blood sample from a vein in your arm. The process is quick and typically painless, though you may feel a slight pinch. The blood is then sent to a lab for analysis.
What Are the Results Measured Against?
Results are compared to standard ranges for your sex and age group, though individual variations exist. Your provider will interpret the results in the context of your overall health and medical history.
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.
High FSH levels may indicate conditions like premature ovarian insufficiency (POI), ovarian failure, or PCOS. Low FSH could suggest pituitary disorders, hypogonadism, or certain genetic conditions. Repeated testing may be needed to track changes over time, especially in fertility planning or monitoring treatment.
Short name
FSH Level
Frequently asked questions
How often should FSH be checked?
Can lifestyle changes affect FSH levels?
Is FSH testing painful?
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