What is it?
Sex hormone binding globulin (SHBG) is a protein produced by the liver. It binds to steroids, such as testosterone and oestradiol and transports them around the body, in the blood. SHBG levels are indicated in the investigation of hirsutism or infertility in women. It is an important biomarker for investigation of reduced libido and erectile dysfunction in men.
Reference ranges
If your indicative SHBG level is lower than the reference range for our laboratory:
It may mean that SHBG is not attaching itself to enough testosterone, meaning that unattached testosterone is going to the body tissues in excessive quantities, rather than remain in the blood.
It can imply hypothyroidism or diabetes (type 2), as well as excesses in cortisol production or general use of steroid medication.
Specifically for men it may imply a testicular problem or disfunction of adrenal/pituitary gland.
Specifically for women it may imply a polycystic ovary syndrome (PCOS), which can lead to reduced fertility. Low SHBG can lead to excessive hair growth or hair loss, menstrual abnormalities or irregularities and skin conditions.
Additionally, lower SHBG levels may be seen in hypothyroidism (thyroid condition), obesity, hyperinsulinaemia and growth hormone excess.
You should discuss this result with your GP if you have concerns or symptoms.
If your indicative SHBG level is higher than the reference range for our laboratory:
If your SHBG concentrations are too high, it may mean the protein is attaching itself to too much testosterone in the blood, leaving insufficient quantities for the tissues. This can lead to a liver disease, hyperthyroidism and eating disorders in both sexes.
Specifically in men it can mean a problem with testicles or pituitary gland that is responsible for producing Thyroid Stimulating Hormone (TSH).
Specifically in women, it can also imply a disfunction of the pituitary gland or a problem with hormone production.
Elevated SHBG levels are also seen in cases of anorexia and malnutrition and can increase with age. Pregnancy or growth hormone/androgen deficiency, hyperthyroidism or liver disease can also explain elevated SHBG levels.
You should discuss this result with your GP if you have concerns or symptoms.
