Luteinizing Hormone

Updated: Sep 28, 2020
Author: Edward Charbek, MD, FCCP; Chief Editor: Thomas M Wheeler, MD, FCAP 

Reference Range

The reference range for luteinizing hormone (LH) is as follows:

Normal findings for luteinizing hormone (LH)

Adult[1]

Male: 1.24-7.8 IU/L

Female:

  • Follicular phase: 1.68-15 IU/L
  • Ovulatory peak : 21.9-56.6 IU/L
  • Luteal phase: 0.61-16.3 IU/L
  • Postmenopause: 14.2-52.3 IU/L

Child (age 1-10 years)[1] :

  • Male: 0.04-3.6 IU/L
  • Female: 0.03-3.9 IU/L
 

Interpretation

Conditions associated with increased LH

See the list below:

  • Hypogonadism

  • Klinefelter syndrome

  • Turner syndrome

  • Anorchia

  • Ovarian failure, or premature menopause 

  • Menopause

  • Precocious puberty

  • Polycystic ovarian syndrome

  • Swyer Syndrome[2]

Conditions associated with decreased LH

Hypothalamic causes are as follows:

  • Kallmann syndrome

  • Isolated idiopathic hypogonadotropic hypogonadism (GnRH deficiency)

  • Stress-related hypogonadotropic hypogonadism (eg, strenuous exercise, anorexia nervosa, bulimia)

Pituitary causes are as follows:

  • Mass lesions (eg, pituitary adenomas, cysts, metastatic disease)

  • Hypothalamic/pituitary surgery or radiation

  • Infiltrative disease (eg, sarcoidosis, hemochromatosis, histiocytosis)

  • Pituitary apoplexy

  • Head trauma

  • Hyperprolactinemia

  • Primary hypothyroidism

Luteal phase dysfunction is another condition associated with decreased LH.

 

Collection and Panels

Specifics for collection and panels are as follows:

  • Specimen type: Blood serum

  • Container: Vacutainer, red/black top

  • Collection method: Venipuncture

  • Specimen volume: 0.6 mL

Related tests are as follows:

  • Follicle-stimulating hormone (FSH)

  • Total estrogens

  • Estradiol

  • Testosterone

  • Progesterone

 

Background

Description

Luteinizing hormone (LH) is a glycoprotein gonadotropin secreted by the anterior pituitary in response to gonadotropin-releasing hormone (GnRH), which is released by the hypothalamus. The same pituitary cells also secrete FSH, another gonadotropin.[3]

LH and FSH are composed of alpha and beta subunits. The alpha subunit is similar in LH, FSH, TSH, and HCG, while the beta subunits differs among the hormones. The specific beta subunit confers the unique biologic activity. LH and FSH bind to receptors in the testis and ovary and regulate gonadal function by promoting sex steroid production and gametogenesis.[4] Both are essential for reproduction in males and females.

LH and FSH play central roles in the hypothalamic-pituitary-gonadal axis, and, thus, conditions related to LH and FSH deficiency can be caused by pathology of either the hypothalamus or pituitary. The two are frequently measured together, along with other hormones. Careful analysis of the presenting problem, the patient’s overall health, and the hormonal profile is often necessary to determine the cause of LH abnormality and, thus, the most appropriate treatment.[5, 6, 7, 8]

Indications/Applications

Indications for testing of LH include the following:

  • Evaluating menstrual irregularities (including anovulatory bleeding)

  • Evaluating suspected hypogonadism

  • Evaluating precocious puberty

  • Predicting ovulation

  • Evaluating infertility

  • Evaluating pituitary disorders