A Testosterone, Free, Direct (EIA) test is a blood test that measures the amount of free (unbound) testosterone in your bloodstream. Free testosterone is the portion of testosterone that is not bound to sex hormone-binding globulin (SHBG) or other proteins and is readily available for use by your body.
There are several reasons why your doctor might order a Testosterone, Free, Direct (EIA) test:
Symptoms of low testosterone: Testosterone is an important hormone for both men and women, and low levels can cause a variety of symptoms such as decreased sex drive, fatigue, muscle weakness, and depression.
Monitoring testosterone replacement therapy: If you are receiving testosterone replacement therapy, your doctor may order a Testosterone, Free, Direct (EIA) test to monitor the effectiveness of your treatment.
Evaluation of certain medical conditions: Testosterone levels may be affected by certain medical conditions such as polycystic ovary syndrome (PCOS), pituitary gland disorders, and adrenal gland disorders.
Evaluation of fertility: In men, free testosterone levels may be a factor in infertility or subfertility.
It’s important to note that testosterone levels can vary throughout the day, and multiple tests may be necessary to confirm a diagnosis of low testosterone. Your doctor will consider your specific medical history and symptoms when deciding which tests to order.