Doctors at Boston Children’s Hospital found that 8.2 percent of the 184 transgender youth seen at their Gender Management Service (GEMS) clinic between 2007 and 2015 were adopted. The overall rate in the state of Massachusetts is 2.3 percent.

Although this phenomenon has been noted independently by several medical professionals, no one knows why this is the case. Daniel Shumer, M.D., who worked at the GEMS clinic and is co-publishing a paper presenting this data, suggests: “Perhaps parents who adopt kids are more open to differences in gender identity—may have less shame in the fact that their child may be transgender, may be more likely to present to clinics for help.”

Adam Pertman, president of the National Center on Adoption and Permanency, points out that “Adopted people of all ages, especially children, are disproportionately represented in clinical settings.” In other words, it may be the case that a higher rate of transgender adopted youth receive care, rather than that a higher rate of transgender youth were adopted.

Other researchers in the field have theorized that a greater openness toward rethinking gender might arise from the relatively more complex identity formation process adoptees undergo.

None of the three transgender adoptees interviewed on this topic by Boston’s NPR station, WBUR, however, said that they felt an overt connection between being adopted and being trans. Jamison Green, immediate past president of the World Professional Association for Transgender Health, said, “People, in trying to understand what transness is and how it manifests and why some of us are this way, will elicit all kinds of conjectures.”