How long will I need to be on blockers?

If you are a young person currently on our blockers-only Pathway, we generally advise that you should wait at least six months before adding hormones to your treatment. This will be discussed on a case-by-case basis with our medical and wellbeing teams. If you are on our masculinising Pathway and your treatment consists of blockers alongside testosterone, once you have started testosterone, we recommend being on blockers for at least 6 months. You may stop them after this stage to see if ther...

I am aged eighteen or over and I want to start gender-affirming care on the NHS. Can I consent on my own behalf?

Yes. Once you have turned eighteen you are legally an adult in the UK and can consent to any treatment, including gender-affirming care.

I am aged sixteen or seventeen and I want to start puberty blockers on the NHS. Can I consent on my own behalf?

Possibly. In the UK, people aged sixteen and over are presumed to be able to consent to medical treatment on their own behalf. However, the judgement of Bell v Tavistock ruled that in some cases clinicians may find it appropriate to involve the court in the referral of a sixteen or seventeen year old for puberty blockers. If this is the case, you may need to apply for a court order to continue with treatment.

I am under sixteen and I want to start puberty blockers on the NHS. Can I consent on my own behalf?

Unfortunately this is unlikely. The UK has a legal provision called Gillick competence (, which means that children can consent to treatment provided they fully understand the consequences of the treatment. However, the judgement of Bell v Tavistock has led the NHS not to accept informed consent from young people in regards to transgender healthcare, even where Gillick competence might otherwise apply. If you ...

I am the parent(s) of a child who wants to start puberty blockers on the NHS. Can I consent on their behalf?

Yes. According to the judgement of ABCD v Tavistock, those with parental responsibility can consent to puberty blockers on behalf of their child. This ruling is legal, but the NHS have as yet failed to update their service specifications accordingly, and so responses to it may not be consistent.

Are gender-affirming hormones reversible?

No. Prescribing these hormones has long-lasting and irreversible implications, however these changes do not occur overnight. Gender affirming hormones are classed as being partially reversible. No doctor would ever choose to actively prescribe such medication unless it was in the best interest of the patient.

How common is breast enlargement or reduction as a side effect of puberty blockers?

Our bodies respond in different ways to puberty blockers. Some patients experience either an increase or decrease in breast size during treatment. While specific data on the frequency of individual side effects are lacking, it is generally accepted that frequent side effects are experienced by 1% to 10% of patients on blockers.

Can a patient stay on puberty blockers for life without being prescribed additional sex hormones?

Hormones are needed for healthy bone development. As such, we do not recommend the prescribing of puberty blockers indefinitely without gender-affirming hormones. Further information about bone density can be found here (

How long have puberty blockers been used?

Puberty blockers have been recommended for over two decades. Initial guidelines for the use of puberty blockers in adolescents were developed in the mid-1990s, and since then have been introduced into international guidance by prominent medical institutions like the World Professional Association for Transgender Health and the Endocrine Society. The use of puberty blockers has thus been a standard part of medical care for many years. Although some countries, like the UK, do not always follow ...

Who are puberty blockers for?

In transgender healthcare, puberty blockers are prescribed to adolescents who are experiencing distress around the onset of puberty. They delay the onset of puberty to allow the patient more time to explore their gender identity and find a way to resolve the distress. GnRH analogues - the medical name for puberty blockers - or just blockers - are also used to treat precocious puberty in children, and infertility and endometriosis in adults. Contrary to popular belief, puberty blockers are ...