For more than three decades, Ms. Dorkenoo waged an international campaign to eradicate the practice known as female genital mutilation. (Courtesy of Equality Now)

Efua Dorkenoo, who for more than three decades waged an international campaign to eradicate the practice known as female genital mutilation, a centuries-old practice that affects millions of girls and women in Africa, the Middle East and immigrant communities around the world, died Oct. 18 at a hospital in London. She was 65.

The cause was cancer, according to an announcement by Equality Now, a women’s rights organization and one of the numerous human rights groups with which she was associated.

Affectionately known as “Mama Efua,” Ms. Dorkenoo was born in the West African nation of Ghana and settled in the 1960s in England. She found work there as a nurse and was a midwife-in-training when she encountered a woman in labor who had undergone female genital mutilation, often referred to as FGM.

The procedure, also known as female circumcision or genital cutting, entails partially or entirely removing the external female genitalia. Within practicing communities, it is regarded as a necessary means of ensuring a girl’s virginity before marriage. Outside those cultures, it is widely considered a human rights violation.

Sometimes carried out with tools including broken glass or razor blades, FGM can lead to severe scarring, chronic pain, infertility, infection and, in some cases, death. Many women who experienced FGM in childhood or adolescence endure lasting psychological trauma. More than 130 million girls and women have been subjected to FGM in the 29 countries where it is most prevalent, according to UNICEF statistics.

Ms. Dorkenoo’s patient in England was so badly scarred that she was unable to deliver her baby through natural childbirth. The encounter was a turning point for Ms. Dorkenoo, who became a public health specialist and dedicated the rest of her life to educating the public about the effects of FGM and to ending its practice.

“It’s all done clandestinely,” she once told The Washington Post. “You can take it from me, if there are people in the U.S. from Africa where it’s endemic, then it’s happening.”

Ms. Dorkenoo encountered resistance and even threats from groups that resented what they regarded as the intrusion of human rights activists on long-standing cultural traditions. “I’m told my offense in speaking out is greater than that of Salman Rushdie and that I should die,” she once remarked to the London Guardian, referring to the novelist who was the subject of an Iranian fatwa.

In the 1980s, Ms. Dorkenoo founded the Foundation for Women’s Health Research and Development, or Forward, a group that has sought to galvanize international efforts to end FGM. In the late 1990s and early 2000s, she worked for the World Health Organization in Geneva.

Among other initiatives, she pushed for stronger opposition to FGM in countries such as England, where the practice has been illegal since the 1980s but was rarely if ever prosecuted.

“No longer can we say we don’t want to upset anyone,” Ms. Dorkenoo insisted. “Of course prevention must be central — but prosecution is the flipside of that same coin. Because in many cases if a parent or guardian feels they can get away with it, they will.”

Former U.S. Rep. Pat Schroeder (D-Colo.), who was a key proponent of a 1996 law prohibiting FGM in the United States, reportedly referred to Ms. Dorkenoo’s efforts in England while shaping the U.S. legislation.

Stella Elliot Efua Yorke was born in Cape Coast, Ghana, on Sept. 6, 1949. In addition to her nursing training, she received a degree from the London School of Hygiene and Tropical Medicine.

She was the author of the book “Cutting the Rose: Female Genital Mutilation,” a volume that received international attention. In 1994, Queen Elizabeth II of England named her an honorary officer of the Order of the British Empire.

A complete list of survivors could not immediately be confirmed.

“We need to get out there and help families to free themselves from this cruel practice,” Ms. Dorkenoo said. “Every day that we sit here, it happens to healthy young children.”