Lab test
SHBG (Sex Hormone Binding Globulin) Levels Blood Test
Below is a plain-language overview of the shbg (sex hormone binding globulin) levels blood test. This blood test measures the level of sex hormone binding globulin, a protein that attaches to sex hormones and affects how much of them can act in the body.
Lab requirements in SHBG (Sex Hormone Binding Globulin) Levels Blood Test
Here is what you need before ordering and completing the SHBG (Sex Hormone Binding Globulin) Levels Blood Test. Review each item and confirm the details with the collection lab.
- Physician's order
- Included. A physician's order is required for lab testing and is provided for you by our partner's physicians — no referral from your own doctor is needed.
- Fasting
- Some tests require fasting or avoiding certain foods or drinks beforehand. You will be informed when you order — confirm the details with the collection lab.
- Preparation
- Preparation instructions can vary, so follow the specific directions provided by the collection lab. This may include timing the test relative to meals or other medications, but always…
- Sample & visit
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Identification
- Bring the lab requisition form from your account. The collection lab may also ask for a government-issued photo ID.
- Turnaround
- 1-3 business days
- Availability
- Our partner lab does not serve ND, RI, NY, NJ, MD or HI. Confirm availability for your location with the collection lab.
Before you go
- Order your test before visiting a lab, then use the requisition form in your account.
- Print the requisition form, or fax it to the lab directly from your account.
- No scheduling is needed — visit the collection lab during its normal business hours.
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Bring a government-issued photo ID in case the lab requests it.
- Results are posted to your secure account within 1–3 business days.
Requirements are summarized from our partner lab's published policies. Preparation and availability can change — confirm current instructions with the collection lab before your visit.
What this test is
Sex hormone binding globulin (SHBG) is a protein made mainly in the liver that binds to testosterone, dihydrotestosterone, and estrogens in the blood. Measuring SHBG helps show how much of these hormones are free to be used by tissues versus bound and temporarily inactive. The test is often used alongside other hormone tests to get a fuller picture of hormone balance.
What it measures
- Sex hormone binding globulin (SHBG) — reflects the amount of this binding protein in the blood
- Calculated free testosterone — sometimes estimated using SHBG and total testosterone
- Calculated free estradiol — sometimes estimated using SHBG and total estradiol
What the test involves
A healthcare professional collects a small sample of blood, usually from a vein in your arm, using a standard blood draw. The sample is then sent to a laboratory for analysis.
Why it is often ordered
A clinician may order this test to help evaluate symptoms that could relate to hormone levels, such as changes in energy, mood, or sexual function. It can also be used to monitor how certain conditions or treatments affect hormone binding.
Preparation
Preparation instructions can vary, so follow the specific directions provided by the collection lab. This may include timing the test relative to meals or other medications, but always defer to the lab's guidance.
How results are reported
Results are typically reported as a numeric value for SHBG, often in nanomoles per liter, and may be compared to a reference range. Reference ranges differ between laboratories, so the range on your report is the one that applies to your sample.
Before you go
- Whether fasting is required before your blood draw
- Any medications or supplements you should pause before testing
- The specific reference range used by the laboratory
FAQ
Frequently asked questions
What can affect my SHBG level?
SHBG levels can be influenced by factors such as liver function, thyroid hormones, body weight, and certain medications. Changes in these factors may raise or lower SHBG independently of sex hormone levels. Your clinician can help interpret what your result means in your specific situation.
Do I need to fast before this test?
Fasting requirements vary depending on the laboratory and the reason for testing. Some labs may ask you to fast, while others do not. Always follow the preparation instructions given by the lab performing your collection.
How is SHBG related to testosterone?
SHBG binds to testosterone in the blood, which can affect how much testosterone is free to enter tissues. A high SHBG level may mean less free testosterone, while a low SHBG level may mean more free testosterone. This test is often used with total testosterone to estimate free testosterone.
Can I get this test without a doctor's order?
In many places, you can order this test yourself, but insurance coverage and state rules vary. It is best to check with the laboratory or your healthcare provider about whether an order is needed. A clinician can help you understand the results.
Related
Related tests
Locations
Order SHBG (Sex Hormone Binding Globulin) Levels Blood Test by state
Choose a state for local context.