First Publication on Puberty Suppression

In 1998, Peggy Cohen-Kettenis and Stephanie van Goozen published an article about a single patient: an adolescent whose puberty had been halted with medication while awaiting further treatment. It was the first scientific description of what later came to be known as puberty suppression for gender dysphoria.

The First Case

The article appeared in the journal European Child & Adolescent Psychiatry under the title Pubertal delay as an aid in diagnosis and treatment of a transsexual adolescent. The authors proposed suppressing puberty with a so-called GnRH agonist. This would give the adolescent time to reflect and would make later physical transition easier.

The 2006 Protocol

The full treatment model was described in 2006 by pediatric endocrinologist Henriette Delemarre-van de Waal and Cohen-Kettenis. It sets out the steps that characterize the Dutch Protocol: puberty blockers from around the age of twelve, sex hormones from age sixteen, and surgery from age eighteen. Conditions included gender dysphoria that had been present since early childhood, no serious mental health problems, and parental support.

The Follow-up Studies

In 2011, the Amsterdam group described the first outcome study, involving seventy adolescents during treatment with puberty blockers. In 2014, this was followed by a study of 55 of them as young adults, after hormone treatment and surgery. According to the researchers, their psychological functioning had improved. Critics point out that the group was small and highly selected, that there was no control group, and that the follow-up took place shortly after surgery. A British attempt to replicate the results at the Tavistock clinic found no improvement in psychological well-being.

How Puberty Blockers Work

Puberty blockers are GnRH agonists, such as triptorelin. They shut down the signal through which the brain instructs the sex glands to produce testosterone or estrogen. As a result, the physical changes of puberty stop. The drugs are administered by injection, usually once every four or twelve weeks. They were not developed for this purpose: since the 1980s, doctors have used them in children with abnormally early puberty and in adults with conditions including prostate cancer. Their use for gender dysphoria is outside the drug’s official approval.

The First Patient

The adolescent described in the 1998 article was assigned female at birth and began receiving a puberty blocker at the age of thirteen, later followed by testosterone and surgery. In 2011, the Amsterdam group published a follow-up description, 22 years after treatment began. By then in their mid-thirties, the patient was functioning well and had no regrets about the treatment. It is one of the few accounts of outcomes over such a long period, but it concerns a single individual. Little is still known about the effects of years of suppression on bones, brain development, and fertility in larger groups.

Significance

In the years that followed, the protocol was adopted by clinics in countries including the United States, the United Kingdom, and Scandinavia, and was incorporated into international guidelines. For a long time, the scientific evidence consisted mainly of the Amsterdam group’s own follow-up studies from 2011 and 2014. The size and quality of that evidence have been the main subjects of criticism since 2020.