These estimates vary so wildly in part because there’s no reliable means of tracking when people change their gender: The Census Bureau still offers only male and female, and many trans people haven’t completely transitioned into living full-time as their expressed gender. Others have so successfully suppressed their history that there’s little evidence they ever lived as anyone else.

One thing, though, is clear: For transgender people, aging into the later years of life can present a unique set of challenges.

Most transgender people have not surgically transitioned—for reasons that include prohibitive cost and decreased sexual function—so when they disrobe in a medical setting, they’re automatically outed, explained Loree Cook-Daniels, the founder of the Milwaukee-based Transgender Aging Network. “That inability to closet even if they want to means we have a much bigger problem in getting trans people to health care,” she said.

Past research has found that many transgender people avoid seeing a doctor for fear of being ostracized. Of those who do seek health care, a 2011 survey of 6,456 transgender people across the U.S. found that 28 percent of respondents had suffered harassment in medical settings, including ridicule or rough treatment. Nineteen percent said that they had been denied care altogether by doctors and other providers, and 50 percent reported having to educate their medical providers on transgender care.

In a more recent study, Tarynn Witten, the director of research and development at Virginia Commonwealth University’s Center for Biological Complexity, examined the concerns of 1,963 transgender survey respondents about their later-life and end-of-life plans. Many participants, she wrote, “stated that they would prefer to die at home rather than be in a palliative care or nursing home facility,” often out of “[fear] of the type of care that they would receive; would they receive the right painkillers, would the care be respectful, would they be abused or violated, would their gender identities be respected, would they be allowed to live their last moments with grace and dignity [?]”

“As I am only part-time in each gender, I am worried that I will be in some situation that will force me to be considered totally masculine,” one of Witten’s study participants wrote, like “being assigned to ‘the boy’s room,’ meaning exile from femininity.”

In nursing homes, gender-segregated spaces like bedrooms and housing wings can be of particular concern to transgender seniors. As Alia Wong recently reported for The Atlantic, the U.S. Department of Education has affirmed that the protections of Title IX extend to transgender students; in July, citing Title IX, the Justice Department filed a statement in support of a transgender student suing a Virginia school district after being required to use an “alternative” restroom. But, Cook-Daniels said, there are currently no similar anti-discrimination regulations in place for nursing homes and other assisted-living facilities.