FSH (Follicle-Stimulating Hormone) in Serum, Plasma, or Other Fluid (Quantitative)
This test measures the amount of follicle-stimulating hormone in your blood or body fluid. FSH plays a key role in regulating reproductive hormones and development in both men and women.
["FSH helps balance reproductive health by signaling the ovaries or testes to produce other hormones."]
Key facts at a glance
- LOINC
- 55611-8
- Short code
- FSH sp1 p chal SerPl-aCnc
- Synonyms
- FSH sp1 p chal 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
What Is Follicle-Stimulating Hormone (FSH)?
FSH is a hormone produced by the pituitary gland, a small organ at the base of your brain. In women, it helps stimulate the ovaries to grow follicles (small sacs containing eggs) and produce estrogen. In men, it supports sperm production in the testes. Your body releases FSH in pulses throughout the day, and its levels can vary depending on your age, health, and reproductive cycle.
Why Might You Need This Test?
Doctors order FSH tests to diagnose or monitor conditions affecting fertility, hormone imbalances, or reproductive health. In women, it may be checked during fertility evaluations, menopause assessment, or to investigate irregular periods. In men, it could be part of evaluations for low testosterone or infertility.
Sample Collection and Preparation
For blood tests, a small sample is drawn from a vein in your arm. If testing fluid from another source (like saliva or urine), follow your healthcare provider’s instructions. Avoid alcohol or certain medications for 24 hours before testing, as they may affect results.
What to Expect Before the Test
No special preparation is usually needed beyond avoiding alcohol or medications that could interfere. If you’re pregnant or have a condition requiring specific diet or activity restrictions, discuss this with your doctor first.
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 early menopause, ovarian failure, or conditions like polycystic ovary syndrome (PCOS). Low FSH could signal pituitary disorders, hypothyroidism, or advanced male aging. Consistently abnormal results warrant further evaluation by a healthcare provider to rule out underlying causes.
Short name
FSH Level
Frequently asked questions
What causes FSH levels to be too high?
What causes FSH levels to be too low?
How often should I get 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