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Test ID: LH Luteinizing Hormone (LH), Serum

Reporting Name

Luteinizing Hormone (LH), S

Useful For

An adjunct in the evaluation of menstrual irregularities


Evaluating patients with suspected hypogonadism


Predicting ovulation


Evaluating infertility


Diagnosing pituitary disorders

Clinical Information

Luteinizing hormone (LH) is a glycoprotein hormone consisting of 2 non-covalently bound subunits (alpha and beta). The alpha subunit of LH, follicle-stimulating hormone (FSH), thyrotropin (formerly known as thyroid-stimulating hormone: TSH), and human chorionic gonadotropin (hCG) are identical and contain 92 amino acids. The beta subunits of these hormones vary and confer the hormones' specificity. LH has a beta subunit of 121 amino acids and is responsible for interaction with the LH receptor. This beta subunit contains the same amino acids in sequence as the beta subunit of hCG, and both stimulate the same receptor; however, the hCG-beta subunit contains an additional 24 amino acids, and the hormones differ in the composition of their sugar moieties. Gonadotropin-releasing hormone from the hypothalamus controls the secretion of the gonadotropins, FSH, and LH, from the anterior pituitary.


In both males and females, LH is essential for reproduction. In females, the menstrual cycle is divided by a midcycle surge of both LH and FSH into a follicular phase and a luteal phase. This "LH surge" triggers ovulation thereby not only releasing the egg, but also initiating the conversion of the residual follicle into a corpus luteum that, in turn, produces progesterone to prepare the endometrium for a possible implantation. LH is necessary to maintain luteal function for the first 2 weeks. In case of pregnancy, luteal function will be further maintained by the action of hCG (a hormone very similar to LH) from the newly established pregnancy. LH supports thecal cells in the ovary that provide androgens and hormonal precursors for estradiol production. LH in males acts on testicular interstitial cells of Leydig to cause increased synthesis of testosterone.


In both males and females, primary hypogonadism results in an elevation of basal follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels.


Postmenopausal LH levels are generally above 40 IU/L.


FSH and LH are generally elevated in:

- Primary gonadal failure

- Complete testicular feminization syndrome

- Precocious puberty (either idiopathic or secondary to a central nervous system lesion)

- Menopause

- Primary ovarian hypodysfunction in females

- Polycystic ovary disease in females

- Primary hypogonadism in males


LH is decreased in:

- Primary ovarian hyperfunction in females

- Primary hypergonadism in males


FSH and LH are both decreased in failure of the pituitary or hypothalamus.

Report Available

Same day/1 to 3 days

Day(s) Performed

Monday through Sunday

Clinical Reference

1. Kaplan LA, Pesce AJ: The gonads. In: Kazmierczak SC, ed. Clinical Chemistry: Theory, Analysis, and Correlation. 3rd ed. Mosby-Year Book, Inc; 1996:894

2. Dumesic DA: Hyperandrogenic anovulation: a new view of polycystic ovary syndrome. Postgrad Ob Gyn. 1995;15:1-5

3. Rifai N, Horvath AR, Wittwer CT, eds: Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018

Method Name

Electrochemiluminescence Immunoassay

Specimen Type


Ordering Guidance

1. The limit of quantitation for this test is 0.01 IU/L. In pediatric settings where greater analytical sensitivity is required, order LHPED / Luteinizing Hormone (LH), Pediatrics, Serum.

2. The preferred test to confirm menopausal status is FSH / Follicle-Stimulating Hormone (FSH), Serum.

Specimen Required

Patient Preparation: For 12 hours before specimen collection do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 0.6 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial within 2 hours of collection.

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
  Frozen  180 days
  Ambient  24 hours

Reference Values


≤4 weeks: Not established

>1 month-≤12 months: ≤0.4 IU/L

>12 months-≤6 years: ≤1.3 IU/L

>6-≤11 years: ≤1.4 IU/L

>11-≤14 years: 0.1-7.8 IU/L

>14-≤18 years: 1.3-9.8 IU/L

>18 years: 1.3-9.6 IU/L



≤4 weeks: Not established

>1-≤12 months: ≤0.4 IU/L

>12 months-≤6 years: ≤0.5 IU/L

>6-≤11 years: ≤3.1 IU/L

>11-≤14 years: ≤11.9 IU/L

>14-≤18 years: 0.5-41.7 IU/L



Follicular: 1.9-14.6 IU/L

Midcycle: 12.2-118.0 IU/L

Luteal: 0.7-12.9 IU/L

Postmenopausal: 5.3-65.4 IU/L

Test Classification

This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
LH Luteinizing Hormone (LH), S 10501-5


Result ID Test Result Name Result LOINC Value
LH Luteinizing Hormone (LH), S 10501-5


If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.

Mayo Clinic Laboratories | Endocrinology Catalog Additional Information: