The 29-year-old supermodel was spotted in New York last week without the bling, while Bloom has also been photographed recently without his.
A friend of the duo has told Famous magazine that the relationship "might be in trouble", the Daily Telegraph reported.
"She’s not wearing her ring, and she’s had a lot on her plate - it could be that somewhere along the way her relationship with Orlando may have slipped between the cracks," the source said. The couple has an 18-month-old child together.
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