Ten years ago, when Dr. Yukari Kato's second child was born seven weeks premature, all she could do was pray he would survive. Happily, after time in a hospital intensive-care unit, he did, and this month he turns 11.

Kato had been working as a psychiatrist in Tottori Prefecture for five years at the time, but the experience became a turning point in her career. A year after her son's birth, she switched to pediatrics, determined to devote herself to saving the lives of children.

"I was so thankful that my son was saved and became healthy, but it didn't feel right just being happy about my own child," she said.