Jarl Mohn, the chief executive of NPR, said on Tuesday that he would take a leave of absence because of health problems. His decision came at a time when the public radio network is grappling with the aftershocks of a sexual harassment scandal.

“As many of you know, last March I suffered a nearly fatal ruptured aorta,” Mr. Mohn, 65, wrote in a note to NPR’s staff. “I returned to work with the blessing of my physician with one important caveat — I cannot allow my blood pressure to rise. Regretfully, the hypertension has returned to a dangerous level.”

Mr. Mohn’s announcement came less than a week after Michael Oreskes, who led NPR’s news division, was forced to resign after The Washington Post published an article that detailed his inappropriate behavior toward two women in the late 1990s, when he was the Washington bureau chief at The New York Times.

“I am deeply sorry to the people I hurt,” Mr. Oreskes said in a statement last week. “My behavior was wrong and inexcusable, and I accept full responsibility.”