Still in an Iranian jail are her fiance Shane Bauer and friend Josh Fattal. The trial for the trio is scheduled to begin Sunday, Feb. 6.
The three were arrested as they hiked near the Iraq border in July 2009. Shourd has said they were hiking in Iraqi Kurdistan and did not intentionally stray over the border with Iran.
Iran has charged the Americans with espionage.
Asked if Shourd, 32, would be returning to Iran, State Department Spokesman PJ Crowley said, '"I'll defer to Sarah Shourd."
A spokesperson for the Shourd family would not comment on her plans. Neither would family members of the other hikers.
Shourd, who is from Oakland, Calif., was released from prison Sept. 14 last year on health grounds after discovering a lump in her breast. Her release was conditional on $500,000 bail. Iran has already said that if she does not return, she will forfeit the bail. It remains uncertain who paid the bail.
In an interview with ABC News after he release last year, Shourd said she would not rule out going back to Iran if it meant proving her innocence and that of Bauer, and Fattal.
"I'm not ruling anything out, but I'm not ruling anything in," Shourd said in the September interview. "I hope that that doesn't have to happen. If that's what it takes to prove that we committed no crime and meant no harm and are absolutely innocent, than I'd be willing to do it."
Since then, several officials involved in the case have told ABC News they do not expect her to return to Iran for the trial.
Today, a public appeal signed by South African Bishop Desmond Tutu, former Peruvian hostage Ingrid Betancourt, former hostage Terry Waite, actor Sean Penn and others called on the Iranian government to free the two remaining hikers, saying "Shane and Josh's freedom is overdue…Every day they remain unjustly imprisoned increases the risk of permanent psychological and emotional damage."