Jan. 23 (UPI) -- Acclaimed science fiction and fantasy author Ursula K. Le Guin died this week in Oregon, her family announced Tuesday. She was 88.
Le Guin's official Twitter account confirmed the author who wrote The Left Hand of Darkness and A Wizard of Earthsea died peacefully at her home in Portland on Monday.
"The family of Ursula K. Le Guin is deeply saddened to announce her peaceful death yesterday afternoon," a post said.
Le Guin's son Theo Downes-Le Guin didn't specify the cause of her death but told The New York Times she had been in poor health for several months.
Born Ursula Kroeber in Berkeley, Calif., on Oct. 21, 1929, Le Guin became known for writing stories about sorcery and interplanetary conflict that infused feminist sensibilities and subverted ideas about gender.
At the LA Review of Books last year, Le Guin described facing struggles working in the genre due to her gender.
"For a woman, any literary award, honors, notice of any sort has been an uphill climb," she said. "And if she insists upon flouting convention and writing science fiction and fantasy and indescribable stuff, it's even harder."
She was first published in 1959 and went on to write more than 20 novels, a dozen books of poetry more than 100 short stories, seven collections of essays, five volumes of translation and a guide for writers.
Her breakout novel A Wizard of Earthsea was published in 1968 and became part of a series in the next few years including The Tombs of Atuan and The Farthest Shore as well as later entries such as Tehanu and The Other Wind released in the early 1990s and 2000s.
In 1969, Le Guin published The Left Hand of Darkness, which was about a planet where people aren't assigned a gender but rather adopt one for brief periods of reproduction.
"I eliminated gender to find out what was left," she said of the book.
The Left Hand of Darkness has been reprinted more than 30 times and many of her works have been translated into more than 40 languages, selling millions of copies worldwide.
Some of her works, including Tales From Earthsea and The Lathe of Heaven, have been adapted into films and television programs.
Le Guin was awarded the Medal for Distinguished Contribution to American Letters at the 2014 National Book Awards. She dedicated the honor to her fellow fantasy and science fiction authors who she said had been "excluded from literature for so long."
She is survived by her son, her husband, Charles Le Guin, her two daughters, Caroline Le Guin and Elisabeth Le Guin, her two brothers, Theodore Kroeber and Clifton Kroeber, and four grandchildren.