luteinizing hormone (LH) in serum

Reference interval

• MALE: 1.4 to 11.1 mIU/mL
• FEMALE:
  • Follicular phase: 1.9 to 11.9 mIU/mL
  • Midcycle peak: 16.6 to 81.1 mIU/mL
  • Luteal phase: 3.2 to 33.9 mIU/mL
• CHILDREN (Pre-pubertal): 0.0 to 2.7 mIU/mL

Principle

The Allegro LH Immunoassay incorporates two monoclonal antibodies with high affinity for LH. The two antibodies, Ab(1) & Ab(2) are selected & prepared to be specific for different & distintic epitopes (sites) on the beta-subunit of the LH molecule. Both antibodies bind without competition or stearic interference from each other, & form a soluble sandwich complex:

Ab(1)__LH__Ab(2)

One monoclonal antibody is radiolabeled for detection, [Ab(2)*], while the other monoclonal antibody is coupled to biotin [Biotin- Ab(1)]. The addition to the reaction mixture of an avidin coated plastic bead allows for a specific & efficient means of binding the sandwich complex to a solid phase via the high affinity interaction between biotin & avidin.

Clinical significance

A wide array of medications affect FSH & LH levels. For instance, drugs containing estrogen or progesterone (e.g. oral contraceptives or estrogen replacement drugs) have been reported to decrease levels of FSH & LH. Similarly, central nervous system (CNS) acting psychoactive drugs which affect the hypothalamus also cause decreased FSH & LH levels.

Like any analyte used as a diagnostic adjunct. LH results must be interpreted carefully with the overall clinical presentations & other supportive diagnostic tests.

Increases

• primary hypogonadism
• polycystic ovary syndrome
• menopause
• pituitary adenoma (rare)

Decreases

• pituitary insifficiency
• Kallman's syndrome
• anorexia nervosa
• fertile enuch (isolated LH deficiency)
• severe stress
• malnutrition
• pharmaceutical agents
  • estrogens
  • psychoactive medications

Specimen

• Determination of LH should be performed on serum. Collect blood sample in a red-top venipuncture tube & allow blood to clot. Centrifuge the sample & separate from cells.
• If assay is performed within 24 hours after collection, the specimen should be stored in the refrigerator at 2-8o C. If the testing will be delayed more than 24 hours, the specimen should be frozen. Mix thoroughly after thawing to ensure consistency in the results. Avoid repeated freezing & thawing.
• Specimens showing particulate matter, erythrocytes, or turbidity should be centrifuged before testing.

More general terms

• luteinizing hormone (LH) in body fluid

More specific terms

• luteinizing hormone (LH) in serum baseline

Additional terms

• luteinizing hormone; lutropin (LH)

Component of

• FSH/LH in serum/plasma
• gonadotropin-releasing hormone stimulation panel
• anterior pituitary evaluation panel
• luteinizing hormone/follicle-stimulating hormone in serum/plasma; lutropin/follitropin in serum/plasma; LH/FSH in serum/plasma

Patient information

luteinizing hormone (LH) in serum patient information