“It’s an experience that never leaves you,” she told The New York Times in 2000. “It needs absolute concentration; it takes up your whole being. And you learn to use your body correctly in a situation of stress.”

There was one secret she seldom shared, however: Her own experience giving birth to her son, Peter, was decidedly unnatural. As Randi Hutter Epstein reported in her book “Get Me Out: A History of Childbirth From the Garden of Eden to the Sperm Bank” (2010), she continually asked her doctor, “Is my baby all right? Is my baby all right,” until the doctor said he could not concentrate with her chatter and gave her laughing gas and an epidural.

“I got everything I raged against,” Ms. Bing told Ms. Epstein. “I had the works.”

Elisabeth Dorothea Koenigsberger was born in a suburb of Berlin on July 8, 1914. Her parents, of Jewish descent, had converted to Protestantism years before her birth, but the family nevertheless felt the virulent anti-Semitism sweeping Germany before World War II. She was kicked out of a university two days into her freshman year, and two of her brothers — a historian and an architect — could not find work because of their Jewish background, she told The Journal of Perinatal Education in 2000.

After Ms. Bing’s father died in 1932, the family left the country; most members settled in England, while one sister moved to Illinois. In London, Ms. Bing studied to become a physical therapist and began work at a hospital. Mostly she helped patients with paralysis, multiple sclerosis and broken bones, but every morning she also visited the maternity ward, to give massages to new mothers and help them exercise. At the time, women were not allowed out of bed for as many as 10 days after giving birth.

She became interested in natural childbirth in 1942 when a patient handed her Dr. Grantly Dick-Read’s influential book “Revelation of Childbirth,” published that year (and later titled “Childbirth Without Fear”). Dick-Read proposed that pain during childbirth was caused by fear, and that a woman could avoid anesthesia by following a series of relaxation techniques aimed at reducing that fear.

Ms. Bing became intrigued and hoped to train with Dick-Read in the north of England, but with the war on and travel all but impossible, she began her own independent study. She read as much as she could and observed obstetricians and their patients — heavily anesthetized women who, she saw, had little control over the birth of their children.

Image Her 1967 book, “Six Practical Lessons for an Easier Childbirth.”

“What I saw I disliked intensely,” she said in her interview with the perinatal journal. “I thought there must be better ways.”