A federal judge in Tennessee on Friday ruled that the state must recognize the legal marriages of three gay and lesbian couples.

U.S. District Judge Aleta A. Trauger's preliminary injunction against the state only covers the lawsuit's three named plaintiff couples. However, Trauger noted in her ruling that marriage bans like Tennessee's were headed to the dustbin of history.

“[P]roscriptions against same-sex marriage will soon become a footnote in the annals of American history,” Trauger wrote.

Among the plaintiffs are Dr. Valeria Tanco and Dr. Sophy Jesty, who married in New York before moving to Knoxville in 2011.

“Getting married not only enabled us to express our love and commitment to one another, but it also provided us with the protections we would need as we started our new lives together,” Dr. Jesty said in a statement announcing the lawsuit in October. Tanco is currently pregnant with the couple's first child.

Tennessee prohibits gay couples from marrying by state law and a constitutional amendment which was overwhelmingly approved by voters in 2006.

Friday's ruling is preliminary and only applies to the six named plaintiffs.