The news will affect 200 staff on the magazine, who were told of the news in a letter handed out by Rosie editor-at-large Heidi Safer, explaining O'Donnell's reasons for quitting.
O'Donnell confirmed the news at a press conference in the US yesterday, citing editorial differences for her decision.
"I am writing with sad news. Today, I notified [G+J USA president and CEO] Dan Brewster that I've been forced to terminate my agreement to produce Rosie magazine with G+J.
"That means that Rosie will end now or in the near future. The decision to discontinue Rosie was a very difficult one, and I spent a long time wrestling with it. In the end, I decided that I could not participate in a magazine that bears my name when I could not be assured it would reflect my vision, values and editorial direction," O'Donnell wrote.
It is thought that the trouble began when former People editor Susan Toepfer took over as editor-in-chief of Rosie this summer.
The magazine is expected to publish its November issue, which is at the printers now, and a December issue before folding.
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