What are puberty blockers and how many children are taking them?

Scared girl sitting on hospital stretcher, waiting for examination in hospital after car accident, crash. Waiting for ER doctor in emergency room.
Young people who may be questioning their gender identity will no longer be prescribed puberty blockers by the NHS. (Getty Images) (Getty Images)

NHS England has confirmed that children will no longer be prescribed puberty blockers at gender identity clinics, after a review found there was "not enough evidence" to show they are safe or effective.

The decision was welcomed by the UK government. Health minister Maria Caulfield said in a statement that this will "help ensure that care is based on evidence, expert clinical opinion and is in the best interests of the child".

But charities supporting trans people and their rights have condemned the new policy, warning that it will cause "irreparable damage" to the health and wellbeing of young trans people.

NHS England commissioned an independent review of gender identity services for children under 18 in 2020. It was led by Dr Hilary Cass and came after a significant rise in referrals to the Gender Identity Development Service (Gids) run by the Tavistock and Portman NHS Foundation Trust.

Dr Cass published an interim report in February 2022 and concluded that Gids, which is set to close at the end of March, did not collect consistent data on what happens to children and young people who are prescribed puberty blockers.

What are puberty blockers?

Puberty blockers can 'pause' or postpone puberty in children. (Getty Images)
Puberty blockers can 'pause' or postpone puberty in children. (Getty Images) (Getty Images/Cavan Images RF)

During puberty, the brain sends out hormones that tell the body what to do, like grow pubic and underarm hair. They also tell the sex organs (ovaries and testes) to start releasing the hormones oestrogen and testosterone.

But, some people experience gender dysphoria, which is a sense of unease that a person may have because of a mismatch between their biological sex and their gender identity.

Until now, children who experience gender dysphoria may have been prescribed puberty blockers, a type of drug that suppresses the release of hormones and can be used to ‘pause’ puberty.

The drug stops their bodies from developing temporarily. Gids said that this gives children more time to consider their options and think more about their gender identity, without the distress that comes with unwanted changes in their body.

After the age of 16, teenagers who have been on puberty blockers for at least 12 months may be given cross-sex hormones, which can cause irreversible changes like breast development or the breaking or deepening of voice.

The NHS warns that long-term cross-sex hormones "may cause temporary or even permanent infertility", and that there is "some uncertainty about the risks of long-term cross-sex hormone treatment".

There are also some cases in which puberty blockers are prescribed for children who are not experiencing gender dysphoria. Much younger children who are going through puberty much earlier than normal - called early or precocious puberty - may also be prescribed the drugs.

How many children are on puberty blockers?

According to the BBC, fewer than 100 young people in England are currently prescribed puberty blockers.

These people, who were prescribed the drugs by the NHS, will be able to continue their treatment despite the new policy.

A report by The Telegraph published last November said that, in the 12 months to July 2023, the number of children beginning puberty blockers on the NHS rose to 83. This was double the average of the two years before.

It is not known how many children are on puberty blockers prescribed by private gender identity clinics.

NHS England said that puberty blockers will be available in the future, but only through a mandatory research trial.

Response to NHS England’s new policy

Many people holding transgender flags high in the sky
Trans charities have raised concerns about the new NHS England policy. (Getty Images) (Getty Images)

The UK government and campaigners in support of restricting access to puberty blockers have backed the decision by NHS England.

But trans charities such as Mermaids and TransActual have condemned the decision and reiterated that trans people "deserve access to high quality, timely healthcare".

A statement by Mermaids said the announcement is "deeply disappointing", adding that it is a "further restriction of support offered to trans children and young people through the NHS, which is failing trans youth".

Meanwhile, TransActual said the decision will "irreparably damage people’s health, wellbeing and life chances". The charity also pointed out that only trans youth who can afford it will be able to access blockers via private healthcare providers, "creating inequality between rich and poor trans people and leading to riskier approaches".

John Stewart, national director of specialised commissioning at NHS England, acknowledged the deeply divisive nature of the subject and said: "Given that the debate is often very polarised, so too were the responses to the consultation.

"Many people said the policy didn’t go far enough in terms of still allowing potential access [to puberty blockers] through research, and others saying clearly they disagreed fundamentally and that these should be routinely available to everyone who believes they need it."

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