She was introduced by Terry Schlossberg, executive director of Presbyterians Pro-Life, as "one of the most astute commentators on culture today."

"I was fighting against you," Mathewes-Green told her audience, composed largely of people committed to ending abortion. "I thought you were stupid. I thought you were nerds. But you were right, and I was wrong."

She said an essay she discovered one day while flipping through Esquire magazine changed her thinking. The author, a doctor, described an abortion procedure he had seen performed on a woman in her 19th week of pregnancy.

"This was a galvanizing essay for me to read," Mathewes-Green said.

She said she realized for the first time that "abortion is a violent, grisly procedure," and knew she could not reconcile her pro-choice stance with her opposition to child abuse, capital punishment and other forms of violence.

"I began to see that abortion was the opposite of feminism, that it undermined feminism," she said, that instead of liberating women, abortion has become "a bizarre new form of oppression."

Women do not really want abortions, she contended, comparing a woman's choice of abortion to an animal's gnawing off his leg to escape from a trap. "Abortion," she said, "is a tragic attempt to escape a desperate situation."

The challenge for pro-lifers, she said, is that society is inured to the reality of abortion. "Women have organized their lives around it," she said. "We're used to it."

She encouraged abortion opponents to help women considering abortion to see that they can live without it, that they have better options. She urged pro-lifers to work to prevent unwanted pregnancies and to support women dealing with unwanted pregnancies.

Mathewes-Green said she was distressed to find, in doing research for her book Real Choices, that 88 percent of women who had abortions did so "because someone they loved told them they should."