Experiencing the world as a different gender than the one assigned you at birth can take a toll. Nearly all research into transgender individuals' mental health shows poorer outcomes. A new study looking specifically at transgender women, predominantly women of color, only further confirms that reality.

What's less clear, however, is whether trans individuals experience more mental distress due to external factors, such as discrimination and lack of support, or internal factors, such as gender dysphoria, the tension resulting from having a gender identity that differs from the sex one was assigned at birth.

Transgender people are often treated extremely poorly by their parents, by their schools, by society at large, and that can leading to problems in school and at work, as well as poverty and increased risk of substance use, according to Ilana Sherer, assistant medical director of the Child and Adolescent Gender Center at the University of California Benioff Children's Hospital in San Francisco.

"The biggest question we need to answer about transgender mental health is this," Sherer wrote in an email. "Is there something inherent about being transgender that makes one more at risk for poor mental health, or is it about how society treats transgender people?"

The study published Monday in JAMA Pediatrics reveals the difficulty in picking apart this question. It examined mental health and substance use among nearly 300 young transgender women in Chicago and Boston.

Only a quarter of the women were white, and all were between ages 16 and 29. The researchers, led by Sari Reisner, a research fellow at Harvard Medical School and Boston Children's Hospital, found that the rate of psychiatric disorders and substance dependence among these women was 1.7 to 3.6 times greater than in the general population.

Four in 10 of the women had a mental health or substance dependence disorder, and 1 in 5 women had at least two diagnosed psychiatric conditions. More than a third of them had experienced depression, and 1 in 5 women had contemplated suicide in the past month. Rates of anxiety, post-traumatic stress, alcohol dependence and other substance dependence also remained higher than average.

At the same time, most of these women were unemployed, more than a quarter lacked health insurance, and many lived in extreme poverty — all mental health stressors and potential effects of discrimination, said Joanna Olson-Kennedy, medical director of the Center for Transyouth Health and Development at Children's Hospital in Los Angeles, the largest transgender youth clinic in the United States.

Those findings contrast significantly from those of another study published this month, which looked at the mental health of 73 transgender children between ages 3 and 12 in Washington state. This younger group did not experience any more depression, and had only slightly more anxiety, than their siblings and non-transgender peers. But the differences between the two studies' participants are also vast.

The Washington state study, which was published in Pediatrics, focused on a much younger and more emotionally supported group. These transgender children were "affirmed in their gender identities in all aspects of their lives," with parental, peer and other social support for their identities, according to that study's lead author, Kristina Olson, an assistant professor of psychology at the University of Washington in Seattle.

The majority came from homes with household incomes above $75,000. By contrast, nearly half the Chicago and Boston women had annual incomes below $10,000 a year. And although the participants in both studies had transitioned, the children had not yet entered puberty.

"I think both of those studies, as all good studies do, leave us with more questions than answers," said Olson-Kennedy "And that's good — that's a sign of good science, and that shapes the other things we need to look at."

One of those things is how the experiences of children with supportive families change as they enter adolescence, especially since many mental health problems emerge then, Olson said in an email. In the newer study, both depression and risk of suicidal thoughts increased with age. Younger women had the lowest rates of mental health conditions, while older women had the highest. But it's unclear why mental health problems increased with age, and whether those findings mean anything for the prepubescent children.

"A lot of the trauma that gender dysphoric children particularly experience is the lack of validation, the kind of ongoing 'No, you're not what you say you are; you are what the church says you are and what your grandmother says you are and what the doctors say you are,' " Olson-Kennedy said. That can also include conflict over use of pronouns, for example.

The young trans children in the Washington study do have validation of their identity as well as other social and economic advantages. No one has studied a population like that into adulthood, and those children might face a different set of pressures, including those that come with not being identifiably trans to casual observers.

"What we don't understand is what gender dysphoria looks like over a lifetime in kids who are supported," Olson-Kennedy said. Difficulties could include higher rates of infertility, deciding when and how to disclose a trans status to a potential romantic partner, finding appropriate health care and covert discrimination, Olson-Kennedy explained.

That could include hearing a transphobic person's ignorant commentary when the speaker doesn't know the trans person's status. "It would be very important to understand those problems to arm people with resiliency tools," Olson-Kennedy said.

"With time, as more research attention is focused on transgender individuals, we will start to get a better understanding of the factors that are associated with better versus worse mental health, and use that information to improve the lives of all transgender people, both before mental health problems emerge and to provide support to reduce or eliminate their impact later in life," Olson said.

Indeed, there is a lot researchers can learn about what not to do by studying transgender people who were socialized in the wrong gender while growing up and only transitioned in adulthood, Olson-Kennedy said.

"What I would love for people to understand is that we are really just starting to get a small understanding of trans youth," she added. "What's exciting is that the data is helping to validate what we know as clinicians, which is that people who are validated and supported in their selfhood are happier, have less mental health challenges and are more successful. We need to stop making people be who we think they should be and start letting them be who they are."

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