Laboratory Methods and Testing of Hormones
There are three different mediums to test hormones. They include saliva, blood, and urine. Each test has its advantages and disadvantages. The saliva sample is collected at home and sent to the lab by the patient. The salivary test also has the advantage of measuring free fraction non-protein pound hormones. This gives the clinician a tremendous advantage because it lets the clinician identify levels of hormones that are available to bind to hormone receptors and induce a transcription response. Salivary tests can also be used to measure circadian rhythms of hormones as well as the ability to measure hormones of an entire menstrual cycle.
Serum hormone tests are usually measurements of hormones bound to proteins which do not give information regarding the amount of active hormone available to receptors. Serum test measure hormones bound to carrier proteins. These levels reflect the potential circulating hormones in the system. They do not differentiate if the hormones are unbound unless the test ordered is a free hormone fraction serum test. The reason salivary tests are less expensive is because the salivary glands completes the steps to unbind the hormone.
Serum tests require extra lab procedures to measure free levels that the salivary glands already conduct. Urine tests are also available to measure hormones. Urinary tests basically measure hormones metabolites as they have passed detoxification. This gives urinary tests advantages as well as disadvantages. The disadvantage of the urinary hormone tests is that it is not reliable to determine the amount or rate of hormones produced by organs and glands. On the other hand, the fact that urinary hormone tests are under the influence of clearance and detoxification means they can actually measure the amount of hormone metabolites.