Marshall explained further in his statement and said: 'One of the few things we know in this area is that most cases of gender dysphoria in children resolve naturally with time, and it's impossible to know ahead of time whose dysphoria will persist into adulthood and whose won't.

'Yet the evidence also shows that nearly all children whose gender dysphoria is treated with puberty blockers to 'buy time' will proceed to take cross-sex hormones and seek other medical interventions with irreversible, lifelong consequences—complications such as infertility, loss of sexual function, increased risk of heart attacks and strokes, bone density problems, risk of altered brain development, social risks from delayed puberty, and mental health concerns,' he added.

Marshall said that children are unable to weigh the 'long-term risks' of the transgender treatments as their brains are still developing and they lack experience. 

'With the stakes so high, the harms so great, and the known benefits so paltry, the Arkansas legislature did not have to embrace an experimental path in lieu of the one that has served the medical profession so well for so long: First, do no harm,' Marshall said.

In late March, during the Senate vote on the bill, state Senator Alan Clark described gender-reaffirming treatments as at best experimental and at worst a serious threat to a child's welfare.' He argued the bill would 'protect children from making mistakes that they will have a very difficult time coming back from.'

'I know that their parents are looking for any kind of answer, and my heart truly goes out to them,'

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'But this is certainly not the answer.'

But transgender advocates backing gender-affirming care say each step is undertaken with the consultation of doctors, therapists and social workers.

Not all teenagers who question their gender identity decide to go through with transition.

But those who consistently identify as transgender can be prescribed puberty blockers. 

Others graduate to cross-sex hormone therapy, a more serious commitment to transitioning. 

A small number opt for some type of surgery with parental consent, but experts say those cases for minors are rare.

'There's a misperception that we automatically set them on this path from puberty blockers to hormones to

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These are very considered decisions. The process can occur over years before surgery is considered,' said Dr. Loren Schechter, a plastic surgeon specializing in gender confirmation surgery.

One Arkansas mother who opposed the bill said her 15-year-old transgender son went through six months of therapy and doctors' visits before beginning hormone therapy.

'Dylan is happy, healthy, confident and hopeful for his future,' Joanna Brandt told the ACLU news conference.

But proponents of the laws say children under 18 should be prevented from receiving any such treatments, accusing transgender advocates of minimizing the side effects and downplaying cases where transgender people regret having made the transition.

The socially conservative American College of Pediatricians, which represents 600 physicians and healthcare professionals, has come out in favor of the legislation, saying affirming gender discordance too early will push young people to transition.

Attorney General Marshall was joined in the brief by the attorneys general of Alaska, Arizona, Georgia, Idaho, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Montana, Nebraska, South Carolina, South Dakota, Tennessee and Texas.  <

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