Multiple sources: 'Beyonce Knowles is pregnant'

E! News claims "multiple sources" close to superstar Beyonce Knowles have told them she is pregnant with her second child.

The 31-years old Beyonce - who gave birth to her first child, daughter Blue Ivy Carter, into the world in January 2012 - is said to be expecting again with her rapper husband Jay-Z.

Speculation about Beyonce's pregnancy first started following her attendance at the star-studded Met Ball earlier this month.

The pop superstar is said to have "carefully" hidden her baby bump in a high-waisted Givenchy gown.

She was then forced to cancel world tour performance in Antwerp, Belgium, after doctors advised her to rest "as a result of dehydration and exhaustion".

Beyonce recently admitted she would love to give her 16-month-old daughter a sibling, because she enjoyed such a close relationship with her younger sister Solange Knowles, 26, when they were growing up.

She said: "I would like more children. I think my daughter needs some company. I definitely love being a big sister."

When pressed on when she may have another child, she added: "At some point, when it's supposed to happen."