Dateline anchor Jane Pauley has broken her silence about the mysterious illness last year that made her face appear alarmingly puffy and kept her off the air for months.

Pauley was afflicted with a form of hives called "delayed-pressure urticaria" that appeared for no known reason and made her face balloon, the anchor told the Ladies' Home Journal

"I had to take steroids to get rid of the swelling, and they made me gain 10 pounds, which on camera looks like 25," Pauley says. 

"Things [would] swell. I could be sleeping or walking and [there it is] on the ball of my foot or something. 

"It's idiopathic," Pauley says. "Which means . . . no known reason." 

Pauley also says she also used her sabbatical from "Dateline" to work on her still-unfinished memoirs and to focus on her three children and her husband, "Doonesbury" cartoonist Garry Trudeau. 

"It would be the last summer before my kids went to college, and Garry and I would take them to Europe," Pauley says. 

"But when they got wind of this plan, they said, ‘You're not going to make us do that, are you?' It became clear Garry and I were dreaming."

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