Caring for Transgender Kids: Is Clinical Practice Outpacing the Science?

Becky McCall, BSc, MSc; Lisa Nainggolan


August 28, 2018

Is Practice Outstripping the Research Evidence?

Many experts assert that in a medical era recognized for its adherence to evidence-based medicine, practice in the management of gender dysphoria is accelerating ahead of the evidence base to support it. The issues around fertility epitomize the uncertainty around the long-term evidence to support the use of hormone blockers.

Nearly 80% of endocrinologists have treated a transgender person, but the same percentage (80.6%) have never received formal training on care for these patients.

But Rosenthal points out that obtaining the necessary evidence to support much of the treatment required will take decades. "We do the best we can with the information available, some of which is directly relevant to young people with gender dysphoria, and some less so."

"It is generally accepted that if young people meet the mental health criteria for being transgender during early puberty, then they are more likely to be transgender as adults," says Rosenthal. "Data show that their quality of life will be compromised without treatment, so they should have the opportunity to avoid the physical changes that do not match their gender identity."

He also points out that pediatric endocrinologists have used pubertal blockers to manage precocious puberty for decades, although those patients receive blockers at a much earlier age and stop once the clinically appropriate pubertal age arrives. He further emphasizes that they are also used to providing estrogen or testosterone at the appropriate age to individuals born without functioning ovaries or testicles.

Evidence for the side effects of pubertal blockers—as used in young people with gender dysphoria—is sparse, but research studies are ongoing. Some data suggest beneficial effects on mental health, whereas long-term effects on bone density and cognitive development are largely unknown.

Bone Health

Rosenthal explains that data demonstrate a fall in bone mineral density Z scores (the level of bone mineral relative to controls) during treatment with pubertal blockers. During normal puberty, there is increased deposition of calcium into bone, but pubertal blocking makes this deposition revert to prepubertal levels. "When the person comes off the blocker and resumes puberty—or the alternative puberty via cross-sex hormones—the rate of calcium deposition into bone [is predicted to catch up]."

A 2015 study[6] that followed bone mineral density development during GnRH analogue therapy in patients with gender dysphoria through 22 years of age found a decrease in bone mineral density Z scores in both natal sexes, but it was more marked in natal girls.

However, much of the data were obtained from patients who started pubertal blockers at almost 15 years of age or in the final stages of puberty. This model of care is different from the one Rosenthal uses, where blockers are initiated at an earlier stage of puberty.

Concerned about delaying puberty too long after starting blockers, Rosenthal has made the decision to not start young people on blockers after age 14 on the basis of evidence of lower bone density in females who have had delayed onset of menstruation and some data, although more inconsistent, in males with delayed puberty. "I feel that the safest thing to do is not have people on blockers alone once they reach 14 years of age. At this point, the patient needs to decide whether to continue with transition or come off the blocker."

Mental and Cognitive Health

In addition, Rosenthal highlights that an adolescent falling out of sync with peers as a result of pubertal blocking may cause adverse mental health effects. With respect to cognitive parameters, there are fewer data still. A study[7] in which participants were put on a pubertal blocker for 1.5 years or not started on blockers at all found a difference between the two groups in terms of executive functioning.

"Given the paucity of data across various physiologic functions in relation to managing gender dysphoria, we initiated a research project funded by the National Institutes of Health 5 years ago to help answer these questions," Rosenthal says.


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