Transgender people exposed to conversion therapy to change their gender identities, particularly as children, are at a greater risk of psychological distress than transgender people who were not treated with conversion therapy, a new study shows.

Researchers analyzed survey responses from more than 27,000 transgender adults across the United States and U.S. territories and military bases, roughly evenly divided between those who had been identified as boys at birth and those who had been identified as girls. People who said they had undergone conversion therapy at any point during their lifetime were twice as likely to have attempted suicide than those who had never undergone such therapies. And those who were subjected to conversion efforts during childhood were four times as likely to have tried to take their own lives, the researchers said.

About 1.4 million adults in the United States identify as transgender, and nearly 700,000 LGBT adults have been exposed to conversion therapy, 350,000 of them as children, according to the Williams Institute, a think tank researching sexual orientation and gender identity issues at the University of California at Los Angeles School of Law. Conversion therapy most commonly consists of psychotherapy from mental health professionals or religious counselors in an attempt to change someone’s sexual orientation or sexual identity, but it can also involve “aversion treatments,” such as inflicting physical pain to deter certain thoughts or behaviors, according to the Williams Institute.

With an increasing amount of research showing such interventions are ineffective and harmful, many major medical and mental health associations have condemned them. And, starting with California in 2012, a number of states and the District of Columbia have banned them in some form.

Senior author Alex Keuroghlian, director of the National LGBT Health Education Center at the Fenway Institute and the Massachusetts General Hospital Psychiatry Gender Identity Program, said the researchers defined conversion efforts broadly, looking at people who had undergone treatment from both secular and religious counselors, but there was no real difference between them.

“Often people assume that the damaging effects somehow are associated with the religious nature of the effort,” Keuroghlian said. “It’s a major finding that it’s not the religious component that’s dangerous in our results — it’s any effort to change someone’s gender identity from transgender to cisgender,” or consistent with the gender they were identified with at birth.

More than 19,000 transgender people in the survey, or about 70 percent, said they had spoken to a professional at some point about their gender identity, and within that group, nearly 20 percent said they had undergone conversion therapy. Those who were exposed to such treatments reported higher instances of severe psychological distress, including suicidal thoughts and attempts, according to the study, which was published Wednesday in the American Medical Association journal JAMA Psychiatry.

William Byne, a professor of clinical psychiatry at Columbia University’s Vagelos College of Physicians and Surgeons who was not involved in the study, said the findings made sense, given the “considerable evidence that many of the mental health disparities experienced by transgender individuals are due to what we refer to as gender minority stress.” He said transgender people experience discrimination and often internalize the message “that they’re not valued equally in society as those who are cisgender.”

Byne said that conversion therapy is especially harmful to children, who “should be building a foundation based on resilience and self-esteem.”

“When this occurs early on, it takes that foundation away from them, or it certainly erodes that foundation,” he said. “If that’s damaged, then you’re going to be less able to deal with gender minority stress as you get older.”

Clinton Anderson, director of the Office on Sexual Orientation and Gender Diversity at the American Psychological Association, said the study has limits because it does not prove causality. He also said the results suggesting that people who underwent treatment as children were at greater risk may be misleading, “because those who report having received treatment for gender identity by a professional before age 10 are likely to be different from those who receive gender identity treatment later.”

“Additional research would help us to better understand the natural course of gender identity development for both cisgender and transgender people across different developmental stages and the impact of different reactions from parents, family, friends, and professionals, some of which we know are negative and rejecting, while others are more positive and accepting,” Anderson said in a statement.

Lead author Jack Turban, resident physician in psychiatry at the Massachusetts General Hospital and McLean Hospital in the Boston area, said he was most concerned by the increased risk of suicide attempts in people who had undergone conversion therapy. “This is a practice that some psychologists still say is an advisable practice for children and is still legal in many states,” he said, adding that the results called for “more legislative and public health attention to this problem, particularly for children.”

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