Even Queen Bey needs a breather every now and then. Beyonce has canceled a planned Tuesday, May 14 concert in Antwerp, Belgium due to dehydration and exhaustion. The "Love on Top" singer's rep told the Associated Press that Beyonce has been advised by doctors to rest -- and may potentially be forced to call off a Wednesday concert at the same venue, Antwerp's Sportpaleis.

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"She is awaiting word from her doctors before making a decision," the rep adds. The arduous Mrs. Carter World Tour kicked off in Serbia last month and is set to continue through August, with a grand finale at Brooklyn's Barclay's Center.

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The concert cancellation comes just one day after the New York Post's Page Six claimed that Beyonce was pregnant with her second child. The singer, 31, and husband Jay-Z are already parents to daughter Blue Ivy, 16 months.

Sources close to the superstar shot down the pregnancy talk to Us Weekly on Monday. "This rumor again?" one insider scoffed, "Don't be silly."

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Still, Beyonce is not opposed to a second child -- eventually. "I would like more children," she said on Good Morning America last week. "I think my daughter needs company."

This article originally appeared on Usmagazine.com: Beyonce Cancels Concert in Belgium Per Doctor's Orders