Young teenagers with extreme gender identity disorder should be given drugs to block puberty so that they don't have to experience distressing changes to their bodies which they perceive to be out of line with their true gender.
So say draft international guidelines issued by the Endocrine Society this week – the first to offer advice to doctors on this controversial issue.
The hope is that by delaying puberty, young teens will be given valuable thinking time in which they can decide if they are sure they want to begin gender reassignment using cross-sex hormones at the age of 16.
Ultimately, this strategy would also make it easier for them to live in their chosen gender. For example, potential male-to-female transsexuals will not have developed the deep voice, facial changes and body hair associated with adult masculinity. Gender-reassignment surgery should be avoided until the age of 18, the guidelines say.
"We recommend that adolescents who fulfill eligibility and readiness criteria for gender reassignment initially undergo treatment to suppress pubertal development," say the guidelines.
They state that treatment should not begin before Tanner stage 2 or 3: when female breasts have begun to bud, and boys have experienced a slight enlargement of the penis and scrotum. This is because the teenager's emotional reaction to these first physical changes can help predict whether they will persist in wanting to change their sex.
The recommendations are largely based on the experience of a clinic in the Netherlands where doctors have so far prescribed puberty blockers to more than 70 under-16s. The youngest they have treated is 11, although the majority are 12 or over.
"We don't have any patient who has regretted their decision on the treatment," says Henriette Delemarre-van de Waal of Leiden University Medical Centre who has helped treat them.
Change of Mind
Clinics in other countries have also begun to offer the treatment, including Canada, Australia, Germany, and a handful of clinics in the US. However, it remains deeply controversial, with countries including the UK refusing to allow medical intervention until the age of 16, by which time puberty is usually in full swing.
At the heart of the issue is the fear that teenagers will change their minds. For example, previous studies have suggested that just 20% of boys who show signs of gender identity disorder in childhood continue to show it into adulthood.
And although the effects of puberty-blockers are reversible - natural puberty would resume if the teenager came off them – there have been few trials exploring the long-term effects of delaying puberty in this way.
"The real question is: if you intervene early in a young person who would otherwise change [their mind], do you reinforce their gender identity disorder? Do you remove the chance for change?" says Russell Viner of the Institute of Child Health in London.
Removal of Choice
There is also the issue of fertility. Blocking puberty in boys before mature sperm have had the chance to develop removes the option of freezing sperm in case they later decide they want to start a family after going ahead with gender-reassignment surgery.
"We recently had the case in the US of a transsexual man who chose to become pregnant, and that may not have been possible if they had had early intervention," says Viner. "When is it reasonable to let a young person remove major life choices?"
However, enduring puberty when you feel you are in the wrong body can cause intense distress, and has even driven some teenagers to contemplate suicide.
"They self-harm, they develop an enormous aversion against their bodies, they isolate themselves and their school performance suffers," says Delemarre-van de Waal.
Marvin Belzer of Children's Hospital in Los Angeles, who has treated several 12 and 13 year-olds with puberty blockers, agrees that there are some difficulties, but that the risks should be weighed against the benefits.
"That's what informed consent is all about," he says. While it's possible that a teenager might change his or her mind, "The question is, can we go back and say, 'yes, but you and your family had informed consent, and we knew that that was one of the risks, but that risk was small'."
The guidelines have been welcomed by transgender support groups who work with young people. "It is an excellent piece of work," says Bernard Reed, a trustee of the Gender Identity Research and Education Society (GIRES), based in Ashtead, UK. He hopes that British doctors will read the guidelines and consider delaying puberty in young teenagers with gender identity disorder.
Meanwhile, in the US, where just a handful of clinics – including Belzer's – offer puberty blockers to young teenagers, the guidelines may encourage more physicians to consider this option.
"This document may spur more to want to treat this," says Belzer. "What I worry is, will they really have the mental health providers [qualified to assess young teenagers]? Many of them will, and hopefully they'll acquire more experience over time."
He also hopes that the guidelines - which offer advice on treating adult transsexuals as well as teenagers - will encourage insurance companies to cover more of the medical costs of treating gender identity disorder. Puberty blockers currently cost around $800 a month, for example.