Luteinizing Hormone (LH) in Serum/Plasma
This test measures the level of luteinizing hormone (LH), a hormone produced by the pituitary gland that plays a key role in reproductive health.
["LH helps trigger ovulation in women and stimulates testosterone production in men."]
Key facts at a glance
- LOINC
- 12675-5
- Short code
- LH 20M p chal SerPl-sCnc
- Synonyms
- LH 20M p chal SerPl-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 1.5
- Ref high
- 9
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83002
- 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 Luteinizing Hormone Used For?
LH levels are commonly checked to evaluate reproductive function, diagnose hormonal imbalances, and monitor conditions like infertility, menstrual irregularities, or pituitary disorders. It may also be used in the evaluation of precocious puberty or to assess the effectiveness of hormone treatments.
How Is This Test Performed?
A blood sample is drawn from a vein, usually in your arm. The blood is then sent to a lab for analysis using an immunoassay method to detect LH levels in your serum or plasma.
Why Might My Doctor Order This Test?
Your doctor may recommend this test if you have symptoms like irregular periods, infertility, early signs of puberty, or if you’re undergoing fertility treatments. In men, it could be ordered to check for low testosterone or other hormonal issues.
What Do My Results Mean?
Results are typically compared to a reference range specific to your age and sex. Abnormal levels may suggest conditions like hypogonadism, polycystic ovary syndrome (PCOS), or other hormonal disorders. Always discuss your results with your healthcare provider.
Reference range
Follicular: 1.5-9.0 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.
Clinical Significance: LH plays a critical role in reproductive health by triggering ovulation in women and regulating sex hormone production in both sexes. Low LH may indicate pituitary or hypothalamic issues, while high levels could signal conditions like ovarian hyperstimulation or tumors. Monitoring LH helps guide treatment for infertility, hormonal imbalances, or endocrine disorders.
Short name
Luteinizing Hormone (Serum/Plasma)
Frequently asked questions
Why do I need this test if I’m not pregnant or trying to get pregnant?
How long does it take to get my LH test results?
Can lifestyle changes, like diet or exercise, affect LH levels?
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