Margaret Grace Schneider, a longtime anti-abortion activist who spent 23 days in jail after a protest at the age of 72, died Thursday of ovarian cancer at the home of a daughter in Woodstock, Va. She was 83.

"She devoted her life to her children and to unborn children," said her daughter Mary Ann Kreitzer of Woodstock. Mrs. Schneider was the mother of 11 children, grandmother of 37 and great-grandmother of 35. She attended rallies opposing abortion across the country.

Born Margaret Croke in Cleveland, she attended Trinity College in Washington, graduating in 1939 with a bachelor's degree in English. She returned to Cleveland to attend law school at Case Western Reserve University, but left after two years to get married.

In a plot orchestrated by her father and an aunt, she ran off to marry childhood sweetheart Raymond J. Schneider, an ensign in the Navy who was about to be sent to Pearl Harbor. The couple married in September 1941.

Three months later, as they were settling in on the island of Oahu, Pearl Harbor was attacked. Mrs. Schneider told of seeing the Japanese planes flying overhead and was soon evacuated to the mainland. She and her husband were members of the Pearl Harbor Survivors Association.

The family moved to Elkridge in 1963.

After their children were grown and her husband had retired from the Navy with the rank of rear admiral, Mrs. Schneider went back to school -- this time to Loyola College in Baltimore, where she received a master's degree in education. She was a substitute teacher for Howard County public schools, her family said.

After the 1973 Supreme Court decision Roe vs. Wade, which legalized abortion, Mrs. Schneider spent a good deal of time on the cause. She raised money for pregnancy centers, presented educational programs in the community and headed her parish anti-abortion group at St. Augustine Roman Catholic Church in Elkridge for more than 30 years.

She also joined what is known as the rescue movement, and in April 1992 spent 23 days in the Erie County jail in Buffalo with Mrs. Kreitzer for blocking an abortion clinic during Operation Rescue's "Spring of Life."

"She was extremely committed, and rightfully so," said her eldest child, Raymond John Schneider, assistant professor of math and computer science at Bridgewater College in Bridgewater, Va.

After Mrs. Schneider's husband died in 1985, she volunteered twice a week at the Little Sisters of the Poor in Catonsville, where she was a regular reader at Mass.

Mrs. Schneider moved into Mrs. Kreitzer's Virginia home after her cancer was diagnosed during the summer. She spent her final days surrounded by family, watching the birds outside the window of her makeshift bedroom.

A Mass of Christian burial will be offered at 9:30 a.m. Saturday at St. Augustine Church, on Old Washington Boulevard.

In addition to her son and daughter, Mrs. Schneider is survived by two other sons, John Michael Schneider of Elkridge and Robert Lawrence Schneider of Columbia; five other daughters, Jeanne Marie Wilhelm of Brunswick, Margaret Grace Schadegg of Leonardtown, Carol Louise Shute of Silver Spring, Susan Joyce Bigelow of Ardsley, N.Y., and Laura Ellen Albers of Sykesville; her grandchildren and great-grandchildren. She was predeceased by two sons, James Michael, who died in infancy, and Thomas Edward Schneider, who died in 1996.