When Beth Scott sought a mammogram two years ago, she had every expectation Aetna, the insurance giant, would cover the cost. But the company told Scott, a transgender woman, she had to pay for the screening because insurance companies don’t cover procedures for women who had been men.

After Scott threatened to file a lawsuit, however, Aetna backed down and last week reimbursed her for the cost of the scan, an important recognition in health care benefits for transgender people, an advocacy group said today.

"If transgender people are being singled out for denial of care that is provided to other individuals, this makes it clear transgender people have to be treated equally under the plan," said Noah Lewis, a lawyer for the New Transgender Legal Defense and Education Fund, a New York-based organization. "Hopefully this will send a message to other insurance companies they can’t keep making these kinds of denials."

Born a male, Scott, 44, of Middlesex Borough, started changing into a woman in 2006, a transition that Lewis said was completed in 2008. Along the way, Scott developed breasts from her estrogen treatments, and she said her doctor suggested she — like other women her age — get a mammogram as part of a routine cancer check.

Health insurance companies have historically not covered medical costs associated with switching genders — like Scott’s hormone therapy or the surgical shaving of her Adam’s apple. But Lewis contended they are obliged to provide coverage for procedures that others of her gender receive.

After Aetna’s first denial of coverage, Scott appealed but was again shot down. The company maintained she was seeking reimbursement for services related to her sex change, though she insisted she was merely seeking coverage for a service every woman receives.

Lewis said insurers often interpret the exclusions to coverage for transgender people "in an overly broad manner."

Scott, who has worked for a software company in Somerset since 2010, said that last week she received an apology from Aetna and the $385 reimbursement she sought. But said it should not have taken threat of a lawsuit to get what she was rightfully due.

In a formal settlement, her employer agreed to cover Scott’s future mammograms as well as prostate exams.

"I feel pleased that the settlement went smoothly and that Aetna apologized," Scott said. "However, I wish this could have been resolved through the appeals process and that the exclusion had not been misinterpreted. I am hopeful that in the future transgender care such as hormones and surgery will be covered as is other medically necessary care."

Cynthia Michener, a spokeswoman for Aetna, said the company administers claims for Scott’s employer, which has a self-financed health plan.

Michener said federal privacy laws prevented her from commenting on Scott’s case, although she noted that mammograms are routinely covered for transgender people.

"Any denial would have been an error corrected by Aetna in administering the claims in the appeals process," she said.

Michener said that since 2009 Aetna has had a policy of covering such procedures as breast-cancer screenings for those who have not had a mastectomy after becoming a man and prostate-cancer screenings for men who became women and retained their prostate.