HONESDALE, Pa. — Even as a girl, Dr. Kate Dewar seemed destined to inherit the small-town medical practice of her grandfather and father. At 4, she could explain how to insert a pulmonary catheter. At 12, she could suture a gash. And when she entered medical school, she and her father talked eagerly about practicing together.

But when she finishes residency this summer, Dr. Dewar, 31, will not be going home. Instead, she will take a job as a salaried emergency room doctor at a hospital in Elmira, N.Y., two hours away. An important reason is that she prefers the fast pace and interesting puzzles of emergency medicine, but another reason is that on Feb. 7 she gave birth to twins, and she cannot imagine raising them while working as hard as her father did.

“My father tried really hard to get home, but work always got in the way,” Dr. Dewar said. “Even on Christmas morning, we would have to wait to open our presents until Dad was done rounding at the hospital.”

Dr. Dewar’s change of heart demonstrates the significant changes in American medicine that are transforming the way patients get care.