Luteinizing Hormone (LH)
Code:9016
| Includes | Luteinizing hormone (LH) |
|---|
Analysis details
Methodology
- Electrochemiluminescence immunoassay (ECLIA)
- Chemiluminescent immunoassay (CLIA)
Expected Turnaround Time
1 day
Special Instructions
- Do not eat for 2–3 hours before the blood draw; water is allowed.
- If approved by the treating clinician and appropriate for care, stop steroid and thyroid hormone medications 48 hours before collection.
- Avoid strenuous exercise and significant emotional stress for 24 hours prior to testing.
- Do not smoke during the 3 hours before specimen collection.
- High-dose biotin can interfere with this assay; discontinue biotin for at least 72 hours before collection.
How to use
Measurement of Luteinizing Hormone (LH), also referred to as luteotropin or interstitial cell stimulating hormone (ICSH), is used to appraise hypothalamic–pituitary–gonadal axis function. Results are interpreted with estradiol, testosterone, FSH, and prolactin to investigate female and male infertility, menstrual and ovulatory disorders, and abnormalities of pubertal development. In women, LH helps determine ovulatory status and is followed to guide and monitor ovulation induction therapy. In men, LH values in conjunction with other hormones assist in distinguishing primary (testicular) hypogonadism from secondary (hypothalamic–pituitary) causes.
Limitations
LH is a pituitary gonadotropin that acts on ovarian theca cells and the corpus luteum in females and on Leydig cells in the testes in males, driving sex steroid synthesis. A preovulatory rise in estradiol precedes the midcycle LH surge by approximately 12 hours, and ovulation follows 12–20 hours after the LH peak. Joint interpretation with FSH, estradiol, testosterone, and prolactin supports differential diagnosis of reproductive and pubertal disorders.
| Unit | mIU/mL | ||||
|---|---|---|---|---|---|
| Reference interval |
| ||||
| Indications | Workup of infertility in women and men, Evaluation of suspected precocious onset of puberty, Monitoring during gonadotropin-based ovulation induction therapy |
Possible Causes of Abnormal Results
Decreased levels
- biotin
Specimen Requirements
| Specimen | Serum |
|---|---|
| Container | Gold/Tiger Top (SST, Gel Separator) |
| Volume | 1 mL (min 0.7 mL) |
| Storage Instructions | Room temperature, Refrigerated, Frozen |
References
Lifshits VM, Sidelnikova VI. Biochemical Analyses in the Clinic: A Reference Manual. 2nd ed. Moscow: Medical Information Agency; 2001. 303 p.
Nazarenko GI, Kishkun AA. Clinical Evaluation of Laboratory Test Results. Moscow: Meditsina; 2006. 543 p.
Chernecky CC, Berger BJ. Laboratory Tests and Diagnostic Procedures. 5th ed. Saunders Elsevier; 2008.