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FSH (Follicle Stimulating Hormone) in Serum, Plasma, or Other Fluid (Quantitative)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of follicle-stimulating hormone (FSH) in your blood or body fluid. FSH is a hormone produced by the pituitary gland that plays a key role in reproductive function.

Quick summary

["FSH helps regulate the menstrual cycle and sperm production; levels can indicate reproductive health or potential fertility issues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
50482-9
Short code
FSH sp6 SerPl-aCnc
Synonyms
FSH sp6 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 This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms or concerns related to fertility, such as irregular periods, difficulty conceiving, or signs of early menopause. It may also be used to monitor conditions like polycystic ovary syndrome (PCOS) or to evaluate hormonal imbalances in both men and women.

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 it’s part of a broader hormonal panel. If testing fluid other than blood (e.g., urine or saliva), follow your provider’s specific instructions.

What the Test Results Mean

Results are interpreted based on your age, sex, and medical history. High or low FSH levels can signal conditions like ovarian reserve depletion, thyroid disorders, or genetic syndromes. Your provider will discuss findings in the context of your overall health.

Common Conditions Linked to FSH Levels

Abnormal FSH can signal reproductive challenges, such as low ovarian reserve (common in perimenopause), hyperprolactinemia (high prolactin hormone), or Klinefelter syndrome (in men). It may also help diagnose conditions like Turner syndrome or hypogonadism.

Reference range

Follicular: 3.5-12.5 mIU/mLN/A

Specimen: serum

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.

◆Associated findings1

Short name

FSH Level

Frequently asked questions

What causes FSH levels to be too high?
High FSH levels may result from conditions like premature ovarian insufficiency (POI), ovarian cysts, thyroid disorders, or genetic factors. In men, it could indicate hypogonadism or Klinefelter syndrome. Always discuss symptoms with your provider.
What causes FSH levels to be too low?
Low FSH can occur with pituitary tumors, hypothyroidism, or conditions affecting hormone production (e.g., Sheehan’s syndrome). In men, it may signal hypogonadism or testicular dysfunction. Your provider will assess other factors, like testosterone levels.
Can lifestyle factors affect FSH test results?
Yes—stress, poor sleep, extreme weight changes, or chronic illnesses (e.g., diabetes) may influence hormone levels. Avoid smoking, excessive alcohol, or certain medications (e.g., birth control) that could interfere with test accuracy. Follow your provider’s guidance.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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