Content warning: This page talks about needles, medical procedures, and blood.
Regular blood testing is important for two main reasons:
1) Blood tests help make sure you’re on the right dose. Knowing how your hormone levels compare to “reference ranges” — what doctors think of as a “normal” level of oestrogen or testosterone for a healthy man or woman — will make sure you’re receiving the right dose.
If your hormone levels are lower than they ought to be, that could mean you’re not getting the changes you want from hormone therapy.
Likewise, if your hormone levels are higher than they should be, that could mean you’re on too high a dose, and could be at risk of serious side-effects. In particular, if you’ve got too high a testosterone level, this can include raised oestrogen levels (as the body can convert excess testosterone into oestrogen).
2) Blood tests help to spot any potential problems before they occur. Hormone therapies come with a number of risks and side-effects, including things like:
- Blood clots
- Liver and kidney problems
- Polycythaemia and erythrocytosis
- Prolactinoma
- Liver dysfunction
- Heart disease
- High blood pressure
However, regular testing can reduce the risk of many of these things by flagging up any potential issues well before they become a serious problem.
The exact risks will depend on what you’re taking, your physiology, and your family history, among other factors. For more information about the risks of hormone therapy, you should talk to your GP or an endocrinologist.
The person prescribing your medication will tell you when your blood tests are due. You might be asked to make sure that you have your blood test taken at a specific time after you take or apply your hormones – make sure you follow these instructions as they are important to getting useful results.
Blood test appointments normally happen either at your GP surgery or at a hospital. You may be asked to book in your appointment for a blood test yourself.
When you first start on hormones, blood testing should be happening very regularly – perhaps every few months. When you have been on hormones for a long time, you may find you only have a blood test once a year. You can find the information given to GPs about how often blood tests should be happening on our Information for Healthcare Professionals pages.
The person prescribing hormones to you should be making sure your blood is being tested regularly. However, sometimes this doesn’t happen. This might happen because there is confusion between different medical professionals about who is responsible for arranging the blood test. When this happens, you may find that you only get blood tests if you ask for them yourself.
If blood tests aren’t being arranged for you when they should be, remind the person who prescribes your hormones about this. If you’re still having problems, and you’re under the care of an NHS gender clinic, you might want to contact them to see if they can offer any help.
Some people find that their GPs are not willing to offer them blood testing. This might be because their GP feels that they aren’t trained to do this, that they aren’t funded to offer it, or they feel that it isn’t their job.
If your GP is refusing to offer you blood tests, you still have options to make sure that your tests are done. These include:
- If you’re under an NHS gender clinic, they may be able to talk to your GP on your behalf, or put you in contact with a different GP who can organise blood tests for you.
- If you’re being seen by a private gender clinic, they may be able to offer you blood tests directly.
- Some sexual health clinics that specialise in LGBTQ+ support may be able to help you.
- If you’re able to afford it, you can pay for your own blood tests. You can book an appointment for this with companies like Randox Health, Medichecks, and Blue Horizon. These companies offer the same ‘venous draw’ tests that are offered on the NHS. You can also order ‘fingerprick’ blood tests from organisations like Sapphic Bison.
- Some organisations offer harm reduction blood testing, particularly for people who have bought their own medication and haven’t been prescribed it by a medical professional. You can find links to harm reduction organisations for people who are self-medicating on our Sources of Support page.
You will also need to check that the levels on your blood tests are correct. In general, your blood test results will tell you the normal ranges for each measurement. You can find all of the published medical guidance for GPs around checking blood levels and prescribing in our Information for Healthcare Professionals pages.
At an appointment for blood testing, a person who is specially trained to take blood (a ‘phlebotomist’) will take a very small amount of blood out of you. This is normally taken from a vein in your arm using a needle, and the blood is drawn into a special container. The whole appointment normally only takes a few minutes.
You can read more about what to expect at a blood test on the NHS website. You can also see a video of exactly what happens in a blood test in this NHS video (content warning: the video contains needles and blood).
If you’re afraid of needles, going to a blood test might be scary. There’s some practical advice on overcoming needle phobia you can read which might help you.
Sometimes there can be problems with getting enough blood out of you. If you find that people are finding it hard to get blood from you, making sure you are well hydrated and warm before the appointment can help.
If staff at your GP surgery find it difficult to get blood from you, you can also try your local hospital’s phlebotomy department. If you ask for your blood test form, you can take it to your local hospital to get your tests done there.
After your blood test, the results of the test will be sent to the person who requested them. This is normally the person who prescribes your hormones. You may be able to use the NHS app to see your test results, or if not, you can ask to see the results. If there is anything that isn’t normal on your blood test results, the person who requested the test will normally contact you to let you know.
It’s very common to have some things outside of normal ranges on blood tests.
You’ll normally have some blood tests taken before you start hormone treatment, and if a reading is outside of normal ranges, this normally resolves itself fairly quickly. This may slow things down for you by a month or two but it’s not a big thing to worry about.
If you’ve already started hormone therapy, it’s very unlikely that your hormones will be stopped completely, even if a blood test has some unusual readings.
If your sex hormone levels are too low at first, don’t worry. Doses are usually started low and gradually increased until levels are right. The person prescribing your hormone medication will normally increase the amount of medication you are taking, or switch you to a different form of the medication. Having higher levels isn’t going to automatically mean you get faster results. The important thing is that if changes aren’t happening as a result of your treatment, you let the person prescribing the medication know.
If your sex hormone levels are too high, this could mean that the measurement was an error. This is particularly common for people using gel, as the blood sample can get contaminated by gel that is on your skin. Make sure you don’t put gel on the arm where blood is being taken from. If your sex hormone levels really are high, this needs fixing – high hormone levels can mean higher risks of health issues, and high testosterone in particular can raise your oestrogen levels. The person prescribing your medication will be able to reduce your dose to manage this.
You may notice very low levels of FSH (follicle-stimulating hormone) and LH (luteinising hormone) on your blood tests – this is expected for some medications used in hormone therapy.
It’s also common for other readings to be outside of their normal values on blood tests. These readings may be measurement errors that resolve themselves over time, or just be normal for your body. However, these blood tests can sometimes indicate some serious side-effects, like polycythemia or prolactinoma, might be happening. This could mean your hormones are paused for a bit while the problem is investigated and/or treated. It’s very unusual to have hormone treatment stopped permanently.
If your hormones are being prescribed by your GP, and they’re not sure how to handle the situation, they can:
- consult the guidance from your gender clinic – for NHS services, they can find these on our Information for Healthcare Professionals pages.
- contact the gender clinic for expert endocrinology advice – many NHS gender clinics have specific email addresses or phone lines for GPs to contact them on for prescribing help.
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This page is based on information originally posted on genderkit.org.uk with permission.
A disclaimer: TransActual do not provide medical, health, or legal advice. The content of this page is intended for information purposes only. It is not a substitute for medical advice, diagnosis or treatment from a medical professional. It is not a substitute for advice from a legal professional. We strongly suggest you consult a healthcare professional or legal professional for specific advice about your situation. TransActual do not advocate or recommend the purchase of any specific product and we do not endorse or guarantee the credentials or appropriateness of any health care provider, any product or any provider of legal services.
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