Irina Ratushinskaya, an indomitable Soviet dissident poet and novelist who, after barely surviving nearly four years in a brutal prison camp, delivered a singular woman’s perspective on the forbidding gulag, died on July 5 in Moscow. She was 63.

Her death was reported by the Russian news media, which said the cause was cancer.

Sentenced in 1983, on her 29th birthday, to the seven-year maximum term for “anti-Soviet agitation and propaganda,” Ms. Ratushinskaya composed some 250 poems in prison, many drafted with burned matchsticks on bars of soap. She memorized them and smuggled them on cigarette paper through her husband to the West, where they were published, and where human rights groups indefatigably lobbied for her release.

She was finally freed in October 1986 in a gesture of glasnost, the more permissive policy pursued by the Soviet leader Mikhail S. Gorbachev. She was released on the eve of the summit meeting between Mr. Gorbachev and President Ronald Reagan in Reykjavik, Iceland.

“The Soviet Union, as Russia was before it, is a land where poet is the proudest and the most dangerous of all professions,” Maria Carlson, a professor of Russian, wrote in 1987 in The New York Times Book Review about Ms. Ratushinskaya’s “Beyond the Limit,” an anthology of her prison poetry.