NASHVILLE (AP) - A federal judge ordered the state of Tennessee on Friday to recognize the marriages of three same-sex couples while their lawsuit against the state works its way through the court system.

U.S. District Judge Aleta Trauger issued the preliminary injunction barring the state from enforcing laws prohibiting recognition of their marriages.

In her written memorandum, Trauger makes clear that her order is only temporary and only applies to the three same-sex couples. A preliminary injunction can only be granted in cases the judge believes the plaintiff will likely win.

"It's the first nail in the coffin of discriminating against same-sex married couples in Tennessee," said Abby Rubenfeld, one of the attorneys for the same-sex couples. "Every single court that has considered these same issues has ruled the same way."

A spokesman for Tennessee Gov. Bill Haslam said in an email that Trauger's decision is still being revi ewed by officials.

"The governor is disappointed that the court has stepped in when Tennesseans have voted clearly on this issue," David Smith said. "Beyond that it's inappropriate to comment due to the continuing litigation."

In Tennessee, marriage between partners of the same gender is prohibited by state law and by a constitutional amendment approved in 2006.

The three same-sex couples were legally married in other states. Their lawsuit did not challenge laws barring same-sex marriage in Tennessee, only those that prohibit recognizing such marriages performed in other states.

Trauger found that the plaintiffs were likely to prevail and that currently they are suffering irreparable harm because of the state's refusal to recognize their marriages. She noted numerous rulings around the country that have struck down bans against same-sex marriage or a state's refusal to recognize the marriages.

One of the attorneys in the case, Regina Lambert, sa id she had just gotten off the phone with plaintiff Valeria Tanco, who is married to Sophy Jesty.

"She's about to give birth at any moment and her mother is on the way from Argentina," Lambert said. "I told her, 'Your mother will be here, and your wife will be your wife, and your daughter will have two parents.' She was just crying on the phone with such joy."

Tanco and Jesty got married in New York in 2011 and now live in Knoxville, where they teach at the University of Tennessee College of Veterinary Medicine.

"Ever since they filed this lawsuit they've been getting flowers from strangers," Lambert said. Their only concern has been the birth of their daughter, whom they have named Emilia.

"This ruling will give them the opportunity to have the joy of expecting a new baby without the fear of something potentially going wrong and ... Sophy being a legal stranger to Emilia," Lambert said.

Ijpe DeKoe and Thomas Kostura also filed the suit. DeKoe is a Sgt. First Class in the U.S. Army Reserves who lives and is stationed in Memphis. He and Kostura, a graduate student at the Memphis College of Fine Arts, married in New York in 2011. Johno Espejo and Matthew Mansell were married in California in August of 2005 after a 10-year relationship. Mansell is an attorney in Nashville. They currently live in Franklin with their two adopted children.

The head of a conservative organization that intervened in the lawsuit said Trauger's decision thwarts the will of 80 percent of Tennesseans who voted to support a state constitutional amendment banning same-sex marriage.

"While today's decision by federal Judge Trauger is not a final ruling, she has clearly signaled her intent to continue the war by unelected federal judges against the rights of states and the citizens of that state to determine what its policies regarding marriage should be," David Fowler, president of the Family Action Council of Tennessee said in an email ed statement.

"If Judge Trauger continues on her present course and strikes down our marriage law, we trust that our state's Attorney General will pursue an immediate appeal."

Multiple judges have overturned voter-approved bans on same-sex marriage in Texas, Oklahoma, Utah and Virginia.

At least 17 states, mostly in the Northeast, and Washington, D.C., allow same-sex marriage. Others may soon follow depending on how federal appeals courts, and eventually the U.S. Supreme Court, rule on state bans that have been overturned.

Six federal judges have issued pro-gay-marriage rulings since the Supreme Court's decision last June that struck down part of the federal anti-gay-marriage law.

U.S. District Judge John G. Heyburn in Louisville, Ky., issued a Feb. 12 opinion that Kentucky's ban on recognizing same-sex marriages violated the Constitution's equal-protection clause because it treated "gay and lesbian persons differently in a way that demeans them. " Unless a federal appeals court steps in and stops the ruling, Kentucky will have to recognize same-sex marriages starting March 20.

Recently, a federal judge in Texas struck down that state's gay marriage ban but immediately delayed the implementation of his ruling pending appeals by the state. In January, the U.S. Supreme Court put a hold on a decision in Utah recognizing same-sex marriages.