Skip to content

FSH (Follicle Stimulating Hormone) in Serum or Plasma

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

This test measures the amount of follicle-stimulating hormone (FSH) in your blood. FSH is a hormone that plays a key role in reproductive health, influencing egg and sperm production.

Quick summary

["FSH helps regulate fertility and hormone balance in both men and women."]

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

Key facts at a glance

LOINC
25639-6
Short code
FSH Ur IRP2-aCnc
Synonyms
FSH Ur IRP2-aCnc
Category
chemistry
Sample
urine
Container
Sterile urine container
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
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What Is FSH Used For?

FSH levels are often checked to evaluate reproductive function. In women, it helps diagnose conditions like polycystic ovary syndrome (PCOS), ovarian insufficiency, or infertility. In men, it may be used to assess low testosterone or sperm production issues.

Who Might Need This Test?

Your doctor may order an FSH test if you have symptoms of hormonal imbalances, such as irregular menstrual periods (in women), low libido, or infertility. It’s also part of screening for conditions affecting hormone production in both genders.

How Is the Test Done?

A blood sample is taken from a vein, usually in your arm. The sample is sent to a lab for analysis. The test measures FSH concentration in your serum or plasma, depending on the lab’s method.

What Are Common Results?

Results are typically reported as a numerical value (in IU/L) but aren’t always provided with reference ranges in plain language. Your doctor will interpret the results in relation to your symptoms and medical history.

Reference range

Follicular: 3.5-12.5 mIU/mLN/A

Specimen: urine

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

Why might my FSH test be ordered before fertility treatments?
Your doctor may check FSH levels to assess your body’s ability to produce eggs or sperm. High or low FSH can indicate problems with ovulation, egg quality, or hormone regulation that might affect fertility treatments.
What could affect my FSH test results?
Several factors can influence FSH levels, including stress, certain medications (like birth control or thyroid medications), chronic illnesses, or hormonal imbalances. If you’re taking medications or have health conditions, let your doctor know before the test.
How long does it take to get my FSH test results?
Results are usually available within a few days to a week, depending on your lab and healthcare provider. Your doctor will explain the results and any next steps during your follow-up visit.
  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