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.

"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."