Pediatrician Dr. Johanna Olson-Kennedy uses a stethoscope and otoscope, of course. But running a clinic for transgender youth means her pediatric medical supplies also include a selection of silicone penises and chest-flattening binders.

Thanks to the openness of Caitlyn Jenner and others, public awareness of transgenderism — and demand for trans-specific medical care like counseling, hormone treatments, and genital surgery — is exploding, even for the youngest of patients. At the 30-plus clinics for transgender youth across the U.S., doctors like Olson-Kennedy can barely keep up with the demand.

Chicago's Lurie Children's Hospital, for example, opened its trans clinic just four years ago but already has 500 patients — and a four-month waiting list. Seattle Children's Hospital opened its clinic in October and immediately got scores of calls. Olson-Kennedy's clinic, the Center for Transyouth Health and Development at Children's Hospital Los Angeles, is the country's largest, treating 725 trans youth from across the western U.S. Five hundred of those patients are Olson-Kennedy's.

Her youngest patient is 3.

What her patients share is the strong, almost certain, belief that they have been born into the wrong body. Their brains tell them they are one gender, their bodies another. Too often, Olson-Kennedy said, these kids have no one to help guide them or ease their pain or even offer routine medical care without disparaging them. "You sit in this room with these young people and see their distress so clearly," said Olson, a 47-year-old California native. "It's not OK to do nothing."

So Olson-Kennedy battles. She fights with insurance companies, tangles with pediatric colleagues who think children are too young to transition, and persuades reluctant parents to help their distressed kids. She's even taken on the authors of What to Expect When You're Expecting for not including a section on transgender children. And now, just as her fledgling field is beginning to gain medical and mainstream acceptance, she's got a new adversary: President-elect Donald Trump, who many fear will erode the recent gains of the transgender community and cut access to the health care they need to transition.

"It's my number one concern right now," Olson-Kennedy said. "I'm very worried."

But there are also signs of hope. Olson-Kennedy is helping lead the first National Institutes of Health grant for research on transgender youth, now in its second year. And she and others hope that data will help win out over discrimination.

Olson-Kennedy's clinic sits on the fourth floor of a bank building on a busy stretch of Sunset Boulevard. In her office with a view of the iconic Hollywood sign, she counsels patients and their parents — a good many of whom have driven or flown from distant states to see her. She can spend hours getting to know a patient before beginning any medical treatment.

The youngest patients receive no medical interventions, just counseling. Olson-Kennedy describes one 18-month-old, born a girl, who understood her gender before her grammar. "I a boy," she repeatedly told her parents. Many young children who experiment with gender roles end up reverting to their birth gender.

But when the gender discomfort persists into adolescence, said Olson-Kennedy, it's usually there to stay. And puberty, when secondary sex characteristics develop, can be a dangerous trigger.

"I've had mothers call me who say their child tries to kill themselves every time they have their period," Olson-Kennedy said. "Parents come in saying, 'My kid tried to cut off his penis with dental floss.'"

Olson-Kennedy's first line of treatment for adolescents is stopping puberty so children and their parents can buy time to sort out what they want to do. Puberty blockers, GnRh agonists like the injectable Lupron or the implant Supprelin, suppress puberty by modifying hormone release. Such drugs have been used off-label safely for more than 30 years to stop early puberty.

Trans doctors say it's critical to stop puberty before the body morphs in ways that are difficult to change — the broadening of shoulders for men, for example, or the rounded hips of women. "Even 14 or 15 is too late," said Dr. Norman Spack, an endocrinologist who founded the country's first transgender youth clinic at Boston Children's Hospital.

Once children are ready to make a permanent change, they can stop puberty blockers and use masculinizing or feminizing hormones. Some trans youth go on to have surgery to remove breast tissue or add breast contours or alter their genitals. Others forego surgery and use binders and packers to alter their body shape.

While some religious groups oppose the process of transitioning — and radio host Laura Ingraham, in the running to be Donald Trump's press secretary, told her listeners to wear adult diapers rather than use public bathrooms with people who are trans — Olson-Kennedy and her colleagues mostly ignore the flack. They say the care they are providing is not only reducing emotional distress but saving lives. Without support and treatment, Olson-Kennedy said, trans kids are a risk for almost everything: depression, self harm, substance abuse, homelessness, HIV, and suicide.

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