1,25-dihydroxyvitamin D (calcitriol)
This test measures 1,25-dihydroxyvitamin D, the biologically active form of vitamin D. It is used to investigate calcium imbalance, kidney disease and...
Sex Hormone Binding Globulin
38.00
This test measures SHBG, a protein that controls how much testosterone and oestradiol are available to the body. It helps assess hormonal balance and fertility.
Turnaround time
1-2 days
Biomarkers count
1
Same-Day Appointments
UKAS Accredited Labs
Book your test
Under 18? Patients under 18 can only be seen at GB Medlabs and Clinilabs, Monday to Friday only.
1
Email
2
Service
3
Details
4
Confirm
{{ emailError }}
Choose Service Type
Home visit
Professional phlebotomist comes to you
+ £{{ home_visit_fee }}
In clinic
Visit our clinic for your test
{{ clinic_visit_fee > 0 ? '+ £' + clinic_visit_fee : 'Free' }}
Home Visit Details
{{ homeAddressError }}
{{ homeTimeError }}
Choose Clinic Option
Select a clinic:
{{ clinic.name }}
{{ clinic.full_address }}
{{ selectedClinic.name }}
{{ selectedClinic.full_address }}
Select a date
{{ timeSlotAlert }}
Select an hour
Available time slots: {{ timeSlots.length}}
{{ slot.preview }}
{{ selectedTime.preview }}
Loading add-ons...
{{ addOnError }}
No recommended add-ons available.
×
{{ addon.name }}
£{{ addon.price }}
{{ addon.excerpt }}
Selected
Selected ({{ selectedAddOns.length }})
£{{ addOnsTotal }}
- {{ sa.name }} £{{ sa.price }}
Included in total above.
Details about Sex Hormone Binding Globulin
What is a Sex Hormone Binding Globulin test?
A Sex Hormone Binding Globulin (SHBG) test measures the level of SHBG in your blood. SHBG is a protein made by the liver that binds to sex hormones, particularly testosterone and oestradiol, controlling how much is “free” and biologically active.
High or low SHBG levels can significantly affect hormone availability even when total testosterone or oestradiol appears normal. This is why SHBG is essential for accurate hormone assessment and calculation of the Free Androgen Index (FAI).
Why do I need an SHBG test?
SHBG plays a key role in hormonal balance, fertility, and metabolic health. Abnormal levels are commonly seen in thyroid disorders, PCOS, insulin resistance, obesity, and liver conditions.
Reasons for testing include:
• Suspected testosterone imbalance
• PCOS symptoms (acne, hair growth, irregular cycles)
• Low libido or fatigue
• Fertility concerns
• Thyroid disorders
• Insulin resistance or metabolic syndrome
• Monitoring hormone therapy
• Liver function concerns
Benefits of the test
1. Determines how much testosterone is usable
2. Essential for calculating Free Androgen Index (FAI)
3. Supports PCOS investigation
4. Helps assess fertility and hormone balance
5. Links hormonal and metabolic health
6. Useful in thyroid disorder assessment
7. Supports accurate interpretation of hormone panels
8. Guides treatment and supplementation decisions
Expanded benefit explanation
Total hormone levels can be misleading without SHBG. Measuring SHBG allows clinicians to understand how much hormone is truly active in the body.
Step-by-step — How testing works
We offer two UK-wide testing options:
Clinic testing
• Choose nearest UK clinic
• Blood sample collected
• Laboratory analysis performed
• Results securely returned
Home visit (+£60)
• Phlebotomist visits you
• Blood sample collected safely
• Sample sent to lab
• Results delivered confidentially
Your results explained
Low levels
Typical UK range: 18–54 nmol/L
Low SHBG may be linked to insulin resistance, PCOS, obesity, or high free testosterone.
Normal levels
Indicates balanced hormone binding and availability.
High levels
High SHBG may be seen in thyroid overactivity, liver conditions, or low testosterone states.
How It Works
Simple steps to get your results
1
Book Online
Choose your test online and book in seconds. Select your preferred clinic location or home visit option.
2
Visit or Test at Home
Attend one of our UK or London clinics, arrange a home nurse visit, or use a finger-prick kit where available.
3
Get Your Results
Your sample is analysed by accredited UK laboratories, with secure results delivered directly to you.
Take control of your health with London Blood Tests
WhatsApp UsHow to Prepare for Your Test
Follow these guidelines for accurate results
Sample Timing
Where possible, attend your blood test between 7am and 12pm. Please wait until any short-term illness or infection has fully resolved before testing. Avoid intense exercise for 24–48 hours beforehand, as this can affect certain markers.
Fasting & Hydration
Fasting is not always required, but some tests may recommend it. If fasting is advised, avoid food for 8–12 hours before your appointment and drink water only. Stay well hydrated, as this helps with sample collection and accuracy.
Medications & Supplements
Continue prescribed medications unless advised otherwise by your clinician. Avoid vitamin, mineral, or biotin supplements for at least 24–48 hours before your test, as these can interfere with results. If you are unsure about any medication or supplement, please let us know before your appointment.
Hormones & Menstrual Cycle
For hormone-related tests, timing within your menstrual cycle may be important. If relevant, follow any specific guidance provided on your test page.
If you have any questions or special circumstances, our team is happy to advise before your appointment.
Frequently Asked Questions
It measures the amount of sex hormone binding globulin in your blood — the protein that binds testosterone and oestradiol. This helps determine how much of each hormone is free and biologically active.
SHBG controls hormone availaoestradiolen if your total testosterone or oestradiol is normal, abnormal SHBG can create symptoms of deficiency or excess by altering free hormone levels.
No fasting is required unless the test is combined with glucose, insulin, or metabolic screenings. SHBG alone does notrequire fasting.
Yes — SHBG is crucial for assessing PCOS, infertility, menstrual irregularities, and androgen imbalance in women. It is commonly combined with testosterone, LH, FSH, and DHEA-S.
Yes. High or low SHBG alters the balance of reproductive hormones, which can disrupt ovulation and sperm production. It is an important test for both male and female fertility assessments.
Elevated SHBG may be due to high oestrogen, thyroid disorders, liver conditions, or certain medications. High SHBG can lower free testosterone even when total levels appear normal.
Low SHBG is often associated with insulin resistance, obesity, PCOS, hypothyroidism, and androgen excess. Low SHBG increases free testosterone and may cause symptoms such as acne and hair changes.
Results are typically available within 1–3 business days, depending on the volume and courier timings.
GP consultation is optional, but recommended if you have hormone-related symptoms or abnormal results. A GP can explain what your SHBG means in relation to your testosterone or oestradiol levels.
Common add-ons include:
Total Testosterone
Free Testosterone
Oestradiol
LH, FSH
Prolactin
Thyroid Panel
DHEA-S
Similar Products in Blood Testing
Discover more options in this category:
17-Hydroxyprogesterone
This test measures 17-hydroxyprogesterone, a hormone involved in cortisol production. It is used to assess adrenal function and diagnose congenital ad...
5 HIAA
The 5-HIAA (5-Hydroxyindoleacetic Acid) blood test measures the amount of 5-HIAA, a breakdown product of serotonin, in the bloodstream. Elevated level...
6-Thioguanine Nucleotides
This test measures 6-thioguanine nucleotide levels to monitor thiopurine medications. It helps optimise treatment effectiveness while reducing toxicit...
7 Sexually Transmitted Infections by PCR
This PCR screen detects seven common sexually transmitted infections with high accuracy. It identifies active infections even when symptoms are mild o...