After conducting evidence reviews, Finland has begun limiting who can access gender-related treatments and Sweden has restricted the use of puberty blockers and hormones to clinical trials. A Norwegian health body and the French National Academy of Medicine have also urged caution.

In the United States, more than 20 Republican-led states have passed laws banning the use of puberty-blocking drugs and hormones, with some making it a felony for doctors to prescribe them. Hundreds of clinicians across the country — including some who have raised concerns about which adolescents should receive gender-related treatments — have denounced the bans, saying such decisions should be made by patients, their families and their doctors.

Background: Data on the effect of blockers is sparse

Last year, the N.H.S. announced that it would be shutting down the country’s only youth gender clinic after an external review showed that the Tavistock Gender Identity Development Service had been unable to provide appropriate care for the rapidly increasing number of adolescents seeking gender treatments. The clinic had seen a sharp rise in referrals, from 250 young people in 2011 to 5,000 in 2021.

Puberty blockers, which work by suppressing estrogen and testosterone, were first tested on children with gender dysphoria in the Netherlands in the 1990s. The Dutch researchers published their first study on 70 children in 2011, finding that the adolescents reported a decrease in depression and anxiety after taking the drugs.