The World Health Organization will no longer classify being transgender as a mental disorder, a long-awaited change.

On Monday, the WHO, an agency of the United Nations, released its latest version of the International Classification of Diseases. It moves all trans-related categories out of mental disorders and into a new category of sexual health conditions.

"The rationale being that while evidence is now clear that it is not a mental disorder, and indeed classifying it in this can cause enormous stigma for people who are transgender, there remain significant health care needs that can best be met if the condition is coded under the ICD," the group says in its report.

"For mental health conditions, ICD codes are especially important since the ICD is a diagnostic tool, and thus, these are the conditions that often garner much of the interest in the ICD," it continues.

Dr. Lale Say, Coordinator of Adolescents and at-Risk Populations Team at the WHO (pictured below), said gender incongruence, defined as “a marked and persistent incongruence between an individual’s experienced gender and the assigned sex," was "taken out from Mental Health Disorders because we had better understanding that this wasn’t actually a mental health condition, and leaving it there was causing stigma."

"So in order to reduce the stigma, while also ensuring access to necessary health interventions, this was place to a different chapter—the sexual health chapter—in the new ICD," she added.

“It’s sending a very strong message that the rest of the world is no longer considering it a mental disorder,” Dr. Michael First, a professor of clinical psychiatry at Columbia University and the chief technical consultant to the new edition of the codebook, said, echoing Say's sentiments. “One of the benefits of moving it out of the mental disorder section is trying to reduce stigma.”

“The intention is to reduce barriers to care,” Geoffrey Reed, a psychologist who coordinated the mental health and behavior disorders section of the ICD, told The New York Times during the crafting of the changes, back in 2016.

The American Psychiatric Association removed “Gender Identity Disorder” from The Diagnostic and Statistical Manual of Mental Disorders (DSM) in 2012.

Say compared the WHO's decision with another one it made back in 1992, to remove homosexuality from the ICD completely.

"This again was based on the scientific understanding that there was no clear evidence that this issue needs to be medicalized," she said of homosexuality.