CHICAGO — Denee Mallon marveled at the view of Lake Michigan from her hospital bed in the Windy City, where she had just made history: The then 74-year-old transgender woman underwent a milestone sex reassignment surgery she’d sought for decades. “Here I am, finally, after all these years,” she said. “It happened.”

Her operation will be one of the first paid for by Medicare after she won a challenge in May to end the government insurance program’s ban on covering such procedures for transgender individuals. Mallon’s victory opened the door for other seniors to access this care and may influence whether more insurers — private and public — will cover them. LGBT advocates also hailed her case as another step forward to securing equal rights for transgender people.

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“I feel congruent, like I’m finally one complete human being where my body matches my innermost feelings, my psyche,” said Mallon, of Albuquerque, New Mexico, two days after undergoing sex reassignment surgery in mid-October. “I feel complete.”

The Medicare ban was imposed in 1989, stemming from earlier information years before that found there was a “lack of well controlled, long-term studies of the safety and effectiveness of the surgical procedures and attendant therapies.” It deemed such treatment “experimental” and noted a “high rate of serious complications.”

But since then, research has found that sex reassignment surgery is a proven therapy for some individuals suffering from gender dysphoria, with decades-long studies and clinical case reports showing positive results, experts say. There is “agreement among professionals in the field that this is effective treatment,” said Jamison Green, president of the World Professional Association for Transgender Health.

The American Medical Association, the American Psychiatric Association and the American Psychological Association are among the professional medical groups that have in the last decade endorsed sex reassignment surgery, which can include a number of procedures such as a complete hysterectomy, bilateral mastectomy and genital reconstruction.

Yet no one challenged the Medicare prohibition until Mallon did.

Long road home

Mallon said she first became aware of her gender identity when she was a child in the 1940s. “People would ask, ‘How is your little girl today,’ and that was me,” she said. “Well, it’s taken me all these years and detours, potholes and whatnot to finally be where I am right now.”

For Mallon, life — work, five kids and three marriages — had gotten in the way of having sex reassignment surgery. When she could afford it in the late 1970s and early 1980s, she couldn’t get her doctors to approve it. They balked, she said, because she was having sex with women — which they felt was inconsistent with her needing the operation. By the time she got the okay in the late 1980s, she could no longer afford it.

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