Megan Busch wanted to be a doctor for as long as she can remember. When she was four years old, she asked her mother, "What do I have to do to be a pediatrician?" Growing up, she had every doctor play set imaginable, and the only Barbie she ever owned came with a white coat and a pink stethoscope. For years, Busch has watched Youtube videos of surgeries to learn what she can. She worked hard in her science classes in high school and worked as a nurse's assistant with a family practice doctor her senior year.

"It's the only thing I've ever wanted to do with my life," Busch said.

But after three years of intense preparation as a pre-medicine Chemistry major at Erskine College, in Due West, S.C., Busch began to worry that her grades, summer research internships, and involvement in leadership positions on campus wouldn't be enough to guarantee her a spot in medical school.

This year, only 44 percent of students who applied to medical school got accepted. If the rising trend of applicants continues, it will be even harder to get in next year. Despite the intense competition for spots and the uncertainty of the reforms hanging over the health care industry, more students than ever want to be doctors. And as the baby boomer generation ages, experts say more doctors will be needed. Medical schools have begun to expand in response to a predicted shortage of physicians, but those increases threaten to create a bottleneck in residency programs, continuing students' uncertainty about the future past their acceptance to medical school.

Like Busch, Amanda Reavis started worrying she might not make it in to medical school when she began her application process last fall. The fear kept her up late at night. Like Busch, Reavis had taken all the right classes and had gotten good grades. But the odds of becoming a doctor were against her.

"You really don't know what's going to happen, because even if you have everything going for you, your application could still be overlooked due to the sheer number of applications," Reavis, a senior at Erskine, said.

Last year, almost 44,000 students applied to medical schools, a 64 percent increase over those who applied in 1988, the lowest number of applicants in the last 30 years. Students' reasons for wanting to be doctors vary, but for Christians, a sense of calling is central. Harvey Havoonjian, a biological sciences professor at Biola University, in La Miranda, Calif., says that although students express concerns about the difficulty of getting into medical school, they are motivated to persevere by a desire to serve: "A lot of students, especially at Biola and other Christian universities, are coming in with a heart for serving within the scope of health care."

Suzanne Gribble, chair of the Biology Department at Grove City College, in Grove City, Pa., notes that many students want to become doctors because of some specific, health-related event that has affected them or their immediate family. Students are passionate about people and service, but their desire to enter medicine often also originates in a particular life experience involving medicine, she said: "What we often see are young people wanting to give back to a community they've been involved with as teenagers or young people."

Doctors diagnosed Brandon Hammond, a junior biology major at Erskine, with a rare heart disease at age 16. After treatment, Hammond resumed a normal life. Asked why he wants to be a doctor despite the long odds of actually getting an MD, Hammond points to his own medical history: "I want to be able to help others because people have helped me, and I want to give back."

Because getting in to medical school is such a challenge, most students are more concerned about clearing that first hurdle than about the effect health care reform may have on their future careers. Biola students voice concern about the future of the health care industry, but not in specific terms, Havoonjian said:"Anyone who claims to know what will happen 10 to 15 years down the line is being vague at best."

Whatever motivates students, the fierce nature of the competition for admission had Busch trembling when she got back her MCAT score. Faced with the likelihood of not being able to enter medical school in the fall of 2011, Busch began to plan for other possibilities. She got two job offers-one from the research lab where she'd worked during the summers and another as an assistant at a private medical practice. But when she saw her score, she thought first about the story of Joshua.

"My score wasn't great," she said. "I was below the national average, and when I first saw it, I thought, that's it-God's going to get me in, and I'm always going to be able to say it was all by His grace and that will be for His glory."

Despite students' increased interest in becoming doctors, industry analysts say the nation is facing a shortage of physicians as more Americans live longer and older doctors retire. The Association of American Medical Colleges (AAMC) recommended in 2002 that first-year medical school enrollment be increased 30 percent by 2015. In response, 90 percent of medical schools have begun to expand or plan to do so within three years. Twelve new schools- including the University of California, Riverside School of Medicine and the Cooper Medical School of Rowan University in NJ- are scheduled to open by 2016.

But increasing the number of medical school spots has only pushed the problem down the line. While medical schools have expanded enrollment by 21 percent since 2009, residency programs haven't been able to keep up with the demand. Medical professionals and health care educators worry that a lack of sufficient funds for graduate medical education could soon leave some young doctors with no way to complete their education.

"The number of medical students has increased, but the number of residency spots have not increased," Mary Brandt, associate dean of Student Affairs at the Baylor College of Medicine, in Houston, Tex. The AAMC is making a huge effort to alert legislators to the need for residency program funding, she said.

Reavis, who is headed to medical school this fall, hopes to work in missions someday as a family doctor. She has at least three years before she needs to start worrying about her residency. Busch, who found out she'd been accepted to the University of South Carolina School of Medicine just weeks before she graduated from Erskine in 2011, is just finishing her first year of training. She has at least two more years before she has to apply for a residency position in emergency medicine, her chosen field. When she does, she likely will face the same fears for her future she had as an undergraduate.

"That's something I'm going to have to worry about in a couple of years, but there's comfort in God," she said. "He's taken care of me this far-He's not going to leave me in a lurch."