You think you are pro-choice, Carole Meyers was saying. But, really, "how pro-choice are you? What does it mean for you? What's your limit? Will you do an abortion on a woman who is 12 weeks pregnant? Twenty-four weeks pregnant?"

What's your limit with birth defects? she asked. "Would you do an abortion at 28 weeks if the baby had a club foot? How about hemophilia?"

Meyers, a 51-year-old obstetrician and genetics expert, has performed hundreds of abortions over the course of her career and, until earlier this year, served as the medical director of Planned Parenthood of Maryland. She loves her work -- it's very rewarding, she said, and women always thank her -- but she doesn't shrink from examining abortion's ethical dilemmas or from setting her own limits. The truth, she told Lesley and the other medical students, is that abortion is not a black-and-white issue, not for patients and not for doctors.

How are you going to feel about a patient who admits she has picketed the clinic in the past? she continued. "What about the woman who comes in for her third abortion and doesn't want to hear about birth control? How are you going to feel about that?"

I'll tell you how I feel, Meyers declared. "I get mad, frustrated, angry."

The doctor's charged words appealed to Lesley, a 24-year-old second-year medical student at the University of Maryland School of Medicine who had helped organize this regional student-hosted, daylong abortion seminar last year. Lesley respected forthrightness and unconventional thinking. Like Meyers, she had never been afraid to reveal doubts. She wanted to think about complicated questions, to hear about the rewards of being an abortion provider as well as the difficulties.

Tall, thin and smartly dressed, Lesley was five months away from starting her third year of medical school, when she would finally begin caring for patients and touring the medical specialties in search of the right one for her. Obstetrics and gynecology was Lesley's No. 1 choice, and in theory, it was a perfect fit. It offered her the chance to form relationships with women and teens, to be their counselor and their surgeon, to provide preventive care and family planning. And it coincided with her politics.

She had joined Medical Students for Choice, an abortion education group with chapters on 135 U.S. campuses, as soon as she arrived at Maryland. The nation's abortion doctors were graying, and unless a new generation took their place, the right to abortion might be rendered meaningless. Lesley imagined herself being part of that new generation. But would her support for abortion translate into action?

"I won't know until I'm faced with doing it, but I think I would absolutely be able to provide [abortions]," she said. "It's walk the walk, instead of talk the talk. I want my actions to be consistent with my words."

Some of those who have had the externship say it was instrumental in their career decision. Audrey Lance, a medical student at George Washington University who wanted to be an obstetrician, said her summer observing abortions at Johns Hopkins Bayview Medical Center and a clinic in Annapolis was life-changing.

"Patients were so grateful," said Lance, who had only vague interest in abortion until she learned about the shortage of providers. "It just became very clear to me that this was where I was needed."

She has since moved on to an obstetrics residency. Those residencies still train the majority of doctors who do abortions, but there has been a successful effort by abortion rights advocates to recruit new kinds of providers, including family doctors, general surgeons, emergency medicine doctors and pediatricians, who get that specialized training at hospitals or abortion clinics. The nonprofit National Abortion Federation says 32 percent of its member-providers are not obstetricians.

Regardless of specialty, doctors who perform abortions sign up for a lifestyle unlike any other in medicine, a subculture replete with drawn blinds, shredders, and security guards at professional conventions. Violence against abortion providers has declined markedly since the 1980s and '90s, when several doctors were killed or injured in shootings across the country and scores of clinics were torched or bombed, according to abortion federation data.

Myron Rose, a longtime College Park abortion provider who spoke at the seminar Lesley attended, wept as he described the difficult search for new office space after his clinic was firebombed in 1984. But that, he assured Lesley and the other medical students, was "antique times."

Even so, those involved with abortion remain extremely cautious. Doctors take cover in the anonymity of large hospitals and debate whether to take their spouses' surnames and how best to protect their children. Some avoid speaking publicly about abortion.

One of Lesley's professors at the University of Maryland is nationally known in the academic world for her clinical trials on RU-486, the abortion pill that won FDA approval in 2000. But she made a deal with her husband that she would not be an activist or be quoted by the media until their toddler is in college. Her mentor's children have been harassed, she said, and she wants to insulate her own child. Not even her neighbors know the type of doctoring she does. "Maybe when I'm 60," she said.

Carole Meyers said she has never been threatened, but she described herself as hyper-vigilant about her safety. More than most people, she notices when a car slows as it drives by her house, and she isn't comfortable sitting in her living room with the shades up. She always keeps her car keys handy.

To Lesley, these lifestyle sacrifices felt distant. "Nobody's called me a baby killer yet," she said. "I don't know what I would do then."