Claire Keyes began her career before the Roe decision, working as a volunteer to help Pittsburgh women get abortions in New York, where the procedure was legal. After the 1973 Supreme Court ruling, she was hired as a counselor in a newly opened Pittsburgh clinic. She remembers the enthusiasm was palpable.

“The physicians who were so eager to work at the clinic had the same feeling,” she said. “That is something that is so remote from the current situation. By the time that there were physicians who were being murdered, it wasn’t something that doctors were eager to do.”

In 1978, she became the director of the Allegheny center, a job she held until 2008. Three doctors worked at the clinic.

“I initially thought I would just provide abortions to women who really needed them,” said Robert Thompson, a doctor who has worked at the clinic for more than three decades. “I realized soon that was a very naive way to think about this. All the women who showed up at the clinic, in some way, needed this. Who was I to be the arbiter?”

Thompson, who estimated that he has performed about 50,000 abortions, says he never expected to end up at the center of a heated national debate — or to have protesters picket his private practice, where he does not perform abortions, or to have his wife draw the curtains at night because of safety concerns.

“We were just coasting along,” he said. “None of us saw this coming.”