Amid a renewed national conversation about childhood vaccinations, Gov. Matt Bevin of Kentucky said this week that he and his wife made sure all nine of their children got chickenpox.

“Every single one of my kids had the chickenpox,” Mr. Bevin said in an interview on Tuesday with a radio station in Bowling Green, Ky. “They got the chickenpox on purpose because we found a neighbor that had it and I went and made sure every one of my kids was exposed to it, and they got it. They had it as children. They were miserable for a few days, and they all turned out fine.”

Experts said that the practice Mr. Bevin described was antiquated, a holdover from the days before 1995, when a vaccine for chickenpox became publicly available. Back then, so-called chickenpox parties were set up to spread the disease from one child to the next, under the belief that contracting chickenpox as a young child was safer than as an adult.

Doctors said the method can lead to dangerous complications or death. Still, Tara C. Smith, a professor of epidemiology at Kent State University in Ohio who studies infectious diseases, said that despite warnings from medical experts and the availability of vaccines, the practice of deliberately exposing children to disease continues.