To understand how medical authorities worldwide came to endorse sex-trait modification (via hormones and surgeries) for children, one must begin with the Dutch. The importance of the Dutch experimentation cannot be overstated: It created a new type of person, the “juvenile transexual,” and laid the foundation for medicalizing youth with gender distress. The dubious claims made in these studies continue to have vastly oversized influence, despite the glaring flaws in their methodology and analysis. The use of drugs to suppress puberty in youth with gender dysphoria was first proposed in the mid-1990s by clinicians in the Netherlands — sold as a way to give children time to explore their feelings about gender before proceeding to the irreversible changes wrought by cross-sex hormones and surgeries. That these same drugs might stop the very neurodevelopment necessary for youth to comprehend the lifelong consequences of these decisions and therefore impede such exploration apparently never occurred to them. Nor were they dissuaded by studies showing that puberty itself resolved dysphoria in youth or that the majority of these kids would become same-sex attracted adults. The drugs, Gonadotropin-Releasing Hormone agonists (GnRHa) — “puberty blockers” — stop the production of sex hormones responsible for the range of development that happens during normal puberty. Previously approved and used for “precocious” (early-onset) puberty in children (8 and younger for females, nine and younger for males) and to treat endometriosis, uterine fibroids, and infertility in females and prostate cancer in males, they’re notoriously known as the drug of choice for chemically castrating serial male sex offenders. The drugs were not, and never have been, approved to treat gender-related distress. Dutch clinicians saw blockers as a means to address the dissatisfaction reported by some adult male transsexuals as a result of not being able to “pass” as female, belied by their height, muscle mass, facial hair, pronounced jawline, Adam’s apple, etc — secondary sex characteristics brought on by puberty. Until the mid 2000s, only seven trans-identifying children in the Netherlands were treated with blockers. A 2006 article on the “Dutch protocol” — unsurprisingly supported financially by Ferring Pharmaceuticals, the manufacturer of the GnRHa drugs — gave the intervention a boost. The “protocol” began with “social transition,” where the child would adopt the appearance of a member of the opposite sex (clothing, hairstyles, name, etc.). After puberty suppression, the adolescent would start on cross-sex hormones at age 16, followed at age 18 by sex-trait modification surgeries (removal of breasts, uterus and ovaries, or to removal of testicles and creation of a neovagina constructed from penile and sometimes colon tissue). Prior to 2000, eligibility for puberty suppression was strict. The candidates were required to have gender dysphoria since early childhood that worsened with the onset of puberty; be psychologically stable and not suffering from other mental health problems (known as “comorbidities”); and have family support. By imposing these criteria, the Dutch believed they could screen for the children likely to have persistent gender dysphoria. Between 2000 and 2008, blockers were prescribed to 111 children in the Netherlands, mostly (but not entirely) following the established “protocol.” Dutch gender clinicians published two highly flawed studies detailing their approach and outcomes, one in 2011 and one in 2014, and then an equally flawed retrospective study in 2023. But even before these studies were drafted, American clinicians brought the Dutch protocol to the U.S. The first youth gender clinic in the U.S. opened in Boston, MA in 2007. Once imported to the U.S., the criteria for early-onset dysphoria, no comorbidities, and family support were abandoned. Notably, the Dutch study results have never been replicated — clinicians at the U.K.’s Gender Identity Development Service (GIDS) tried and failed, suppressing the results until the clinic was taken to the High Court of Justice for England and Wales.