Last October the American Academy of Pediatrics (AAP) gathered inside the Anaheim Convention Center in California for its annual conference. Outside, several dozen people rallied to hear speakers including Abigail Martinez, a mother whose child began hormone treatment at age 16 and died by suicide at age 19. Supporters chanted the teen’s given name, Yaeli; counter protesters chanted, “Protect trans youth!” For viewers on a livestream, the feed was interrupted as the two groups fought for the camera.

The AAP conference is one of many flashpoints in the contentious debate in the United States over if, when, and how children and adolescents with gender dysphoria should be medically or surgically treated. US medical professional groups are aligned in support of “gender affirming care” for gender dysphoria, which may include gonadotrophin releasing hormone analogues (GnRHa) to suppress puberty; oestrogen or testosterone to promote secondary sex characteristics; and surgical removal or augmentation of breasts, genitals, or other physical features. At the same time, however, several European countries have issued guidance to limit medical intervention in minors, prioritising psychological care.