It won't be clear until university officials review the bids what aspects of sex reassignment surgery would be covered. Officials asked insurance companies for proposals that would cover surgery costs up to $100,000.

Kalra said insurers often use adding transgender coverage as a way to increase premiums, but he said that was based on "faulty logic" because so few people take advantage of the benefit.

"We end up with a situation that makes it look like transgender students, in this case, are costing 'everyone else' more money, when that's really not the case at all," he said.

The amount that it can add to the premium can vary widely based on what's covered, if there is a co-pay and other factors, said James R. Napoli, an attorney for the American Benefits Council, a group that lobbies for benefits legislation favorable to employers. He did not have information on how much adding such coverage typically adds to a plan.

"It certainly is going to add to the general cost of the plan," he said. "Whether that cost is then borne by the participants on the plan, there's a lot of factors that go into that."

But more are adding the coverage, Napoli said. "Employers are wanting to have the appearance of being more inclusive."

No Fortune 500 companies offered coverage specific to transgender people in 2002, when the Human Rights Campaign began tracking the issue, said Deena Fidas, who directs the workplace equality program for the gay-rights group. Instead, it was often listed among the exclusions alongside cosmetic procedures, she said.

In 2008, the American Medical Association passed a resolution endorsing employer health coverage of sex reassignment surgery.

By 2009, 49 companies tracked by the campaign offered transgender health benefits. Now, 340 of those firms offer transgender health benefits — about a quarter of all Fortune 500, Fortune 1000 and large law firms in the country, Fidas said.

Five of the six large companies based in Maryland that the campaign tracks have added the benefit since 2012, including Lockheed Martin and Marriott International in Bethesda, Choice Hotels International in Silver Spring, and food services provider Sodexo Inc. in Gaithersburg. DLA Piper, a global law firm with a large presence in Baltimore, also offers the benefit.

"Not only has it opened up the conversation and the clear view on the part of insurance companies that there's a demand out there, it gave a lot of student groups a major arrow in their quiver when advocating for this because this conversation has become more mainstream," Fidas said. "There aren't a lot of companies left that are actively resistant. Some are slower than others."

Booz Allen Hamilton Inc., a defense and technology contracting firm with headquarters in Northern Virginia, has offered sex reassignment surgery coverage for its 23,000 employees for about five years. No aspect of the gender reassignment is denied, company officials said.

"When you include transgender benefits, it signals to other employees that this a firm that will care for its employees," said James Fisher, a Booz Allen spokesman. "So even though you may not use the benefit, it's a signal to a new hire about what kind of company this is, in terms of support for its employees."

For employees to get sex reassignment surgery covered, they typically must be diagnosed with gender identity disorder first, Fidas said. And some aspects of sex reassignment surgery that are still considered cosmetic — making an Adam's apple less prominent, or shifting the planes of the face — aren't covered under many insurance plans.

Transgender advocates also hope that the federal Affordable Care Act, which prevents insurers from denying coverage on the basis of pre-existing conditions, will bolster their case for expanded coverage.

State insurance commissioners in Oregon, California, Vermont, Colorado and Washington, D.C., have issued bulletins, citing Obamacare, that a person's gender identity cannot be a reason to deny them coverage.

"In the past, simply being transgender was frequently considered a pre-existing condition and a reason for people to be denied coverage or be charged higher premiums," said Kellan Baker, associate director of the LGBT Research and Communications Project at the Center for American Progress, a liberal think-tank.

"There is a lot of hope and expectation that things will get better for transgender people as the Affordable Care Act continues to roll out and we have this national conversation," Baker said.