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

Conditions associated with increased LH

See the list below:

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

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]}