Study Reveals Effects of Puberty Blockers at Controversial UK Gender Clinic

A new U.K. study found that administering puberty blockers to children wanting to transition can impact height growth and bone density, the Daily Mail reports.

The study, published on Tuesday by academic journal PLOS ONE, was conducted at a clinic in the U.K. Subjects enrolled in the study between 2011 and 2014, comprised of 44 subjects, ranging from 12 to 15-years old, with severe and persistent gender dysphoria for at least five years beforehand. The study's primary purpose was to examine the impact of puberty-blocking drugs called gonadotropin-releasing hormone analogues (GnRHa), which have been administered to children who wish to change their sex to match their gender identity.

GnRHa only halts puberty and does not initiate physical transitioning. Researchers found that while the drug impairs both height growth and bone density, they also expect both to resume either naturally or with the administration of hormones from age 16 onward.

Participants in the study were subjected to psychological and physical assessment for two years before taking part. Subjects reported being happy and having good family relationships and friendships after their puberty-blocking treatment began. The study's authors say the only negatives include side-effects of GnRHa they had anticipated – headaches, hot flashes, fatigue, loss of libido, and low moods. All of the subjects said they wished to continue the puberty-blocking treatment.

The report also states that children were highly likely to have suffered "severe psychological distress" if they had not been undergoing the puberty-blocking treatment and were, instead, allowed to progress through puberty, suggesting the impact of puberty on exacerbating gender dysphoria.

However, the study did not consist of a control group, which can be problematic in making absolute determinations from the researchers' findings. The authors acknowledge this and say that more extensive, long-term studies are necessary.

Dr. Polly Carmichael, an author of the study, said it "adds to our understanding of the best way to support these young people. The results show patients' experience on the blocker is positive overall and there were no unexpected adverse events."

Another author of the study, Professor Russell Viner, said the researchers "followed rigorous ethical guidelines" and have placed their data in public domain "to allow other researchers to replicate our main findings."

These assertions about the study's quality come after Tavistock, the clinic where the research was conducted, had been embroiled in a legal battle last year. Keira Bell took Tavistock to court, arguing that such treatments can lead to fertility issues and, therefore, children cannot give informed consent. Bell had begun taking puberty blockers at age 16 before deciding to discontinue treatment. The court ruled in her favor, saying that children under age 16 need to know and understand "the immediate and long-term consequences."

However, research on puberty blockers points to a positive impact on the mental health of trans adults who received the treatment in adolescence – including a decrease in suicidal ideation, depression, and emotional and behavioral problems.