Description
Also known as: Testosterone-estrogen Binding Globulin (TeBG).
SHBG is a protein produced by the liver. It transports testosterone, dihydrotestosterone (DHT), and estradiol in the blood.
SHBG level is affected by age and sex, by decreased or increased testosterone or estrogen production, and can be affected by certain diseases and conditions such as liver disease, hyperthyroidism or hypothyroidism, and obesity.
SHBG test is prescribed in order to evaluate the status of a patient’s androgens - the male hormones. With men, the concern is testosterone deficiency, while with women the concern is excess testosterone production.
SHBG and testosterone levels may be ordered on an adult male to help determine the cause of infertility.
In women, small amounts of testosterone can disrupt the balance of hormones and cause symptoms such as amenorrhea, infertility, acne, and hirsutism.
Its concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.
Purpose of the test
The purpose of this test is to evaluate the level of SHBG in blood in order to evaluate whether the concentration of SHBG is affecting the amount of testosterone available to the body’s tissues.
Reference range values
nmol/L
Male 13 – 71
Female 18 – 114 (non-pregnant)
Children
Males
Tanner Stages: Age, mean nmol/L
Stage I: 7.1(pre-pubertal) 28-150
Stage II: 11.5 44-160
Stage III: 13.6 5.5-163
Stage IV: 15.1 13-88
Stage V: 18.0 10-60
Females
Tanner Stages: Age, mean nmol/L
Stage I*: 7.1(pre-pubertal) 39-176
Stage II: 10.5 7.2-107
Stage III: 11.6 28-171
Stage IV: 12.3 28-149
Stage V: 14.5 20-130
Abnormal findings
High levels of SHBG in blood ussually means that it is likely to be less free testosterone available to the tissues than is indicated by the total testosterone. If SHBG concentrations are decreased, more of the total testosterone is “bioavailable” - not bound to SHBG.