The doctors privately recognized these false self-diagnoses as a manifestation of social contagion. They even acknowledged that suicide has an element of social contagion. But when I said the clusters of girls streaming into our service looked as if their gender issues might be a manifestation of social contagion, the doctors said gender identity reflected something innate.

To begin transitioning, the girls needed a letter of support from a therapist—usually one we recommended—who they had to see only once or twice for the green light. To make it more efficient for the therapists, we offered them a template for how to write a letter in support of transition. The next stop was a single visit to the endocrinologist for a testosterone prescription.

That’s all it took.