Is Beyonce pregnant with baby number 2? The American songstress, who is allegedly expecting another baby, has fuelled further pregnancy rumours when she cancelled a concert in Belgium on doctor's orders.

The 31-year-old Grammy winner has cancelled her concert in Antwerp, which is part of her Mrs. Carter World Tour, on Tuesday because of dehydration and exhaustion.

"Beyonce has been advised by her doctors to rest as a result of dehydration and exhaustion and will not be able to perform in Antwerp, Belgium tonight. She is awaiting word from her doctors before making a decision on the second Belgium date scheduled for May 15," her publicist told AP.

"Tonight's show will be rescheduled as soon as possible and ticket holders should keep their tickets to be used with the rescheduled date. Other tour dates are not expected to be affected."

It should just be a case of a singer getting sick and cancelling a show, but according to reports, it is more than that.

Multiple sources told NY Post's Page Six that Beyonce and her rapper superstar husband Jay-Z are expecting another child. The insiders confirmed speculations after the Met Gala last week, wherein the "Crazy in Love" singer wore a Givenchy gown with a high, belted waist that camouflaged her tummy.

However, pictures from her recent tour stops have emerged online, showing that Beyonce might have been sporting a baby bump under her costumes.

Beyonce, 31, gave birth to Blue Ivy Carter, on January 7, 2012 in New York. Her daughter recently joined her on stage at the O2 Arena in London.