The Economist February 20th 2021 65
Science & technologyGender medicineArrested development
G
ender dysphoria—the miserable
feeling of being at odds with one’s
sex—is one of the fastest-rising medical
complaints among children. America had
one paediatric gender clinic in 2007. It now
has at least 50. The sole paediatric gender
clinic for England and Wales, known by its
acronym, gids, has seen referrals rise 30-
fold in a decade. A similar pattern is evi-
dent across the rich world.
Many attending such clinics are given
gonadotropin-releasing hormone (gnrh)
agonists, or “puberty blockers”. These
drugs, licensed to treat cancers of the
breast and prostate, endometriosis and
“central precocious puberty”—a rare con-
dition in which puberty starts far earlier
than normal—are prescribed off-label to
stop the signals that stimulate the testicles
or ovaries to ramp up sex-hormone pro-
duction. The idea is to delay puberty, buy-
ing time for patients to decide whether to
proceed to cross-sex hormones and sur-
gery with the aim of “passing” as adult
members of the opposite sex.
All drugs offer a mix of harms and bene-fits. But despite their popularity, the ef-
fects of puberty blockers remain unclear.
Because they are not licensed for gender
medicine, drug firms have done no trials.
Record-keeping in many clinics is poor. A
2018 review by researchers at the Universi-
ty of Melbourne described the evidence for
their use as “low-quality”. In December
British judges likewise flagged the lack of a
“firm evidence base” when ruling that chil-
dren were unlikely to be able to give mea-
ningful consent to taking them. Britain’s
National Health Service recently withdrew
a claim, still made elsewhere, that their ef-
fects are “fully reversible”.
The studies that do exist are at once
weak and worrying. The day after the court
ruling, gidspublished a study that foundchildren were happy to receive the drugs.
But there was little other evidence of bene-
fit—not even a reduction in gender dys-
phoria. Two older studies of Dutch pa-
tients given puberty blockers in the 1990s
found that gender dysphoria eased after-
wards. But without a control group, it is
impossible to tell how patients would have
felt had they not taken the drugs.
A 2020 paper analysed responses to an
online survey and concluded that people
who had taken puberty blockers were less
prone to suicidal thoughts. But online sur-
veys capture convenient samples, not rep-
resentative ones. People may answer re-
peatedly, or at random. Much of the data
appeared to be misreported: many who
said they had taken puberty blockers were
too old to have plausibly done so.
In the absence of direct, robust evi-
dence, researchers can try to extrapolate
from other findings. Off-label prescribing
is common in paediatric medicine, be-
cause drug firms do not generally like run-
ning trials on children. So doctors look for
second-hand evidence from elsewhere to
guide their decisions. One source is stud-
ies that look at how gnrhagonists are
used to treat other conditions.
Interrupting normal adolescence is not
the same as treating cancer, endometriosis
or precocious puberty. Nevertheless, data
from these conditions have flagged un-
pleasant side-effects. Men who take gnrh
agonists lose energy and sexual desire.
(This is why some countries prescribePrescriptions for puberty-blocking drugs are on the rise. There is little solid
evidence about their effects→Also in this section
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