TORONTO - Gossips have been buzzing over Jennifer Lopez's bulging belly and fans in Toronto will get an up-close look at the superstar tonight when she takes the stage with husband Marc Anthony.

Lopez is rumoured to be pregnant with twins, but has yet to confirm the whispers despite her protruding tummy.

Us magazine reported Wednesday that the singer is about four months along. One source told the magazine that Lopez's mother is proudly telling people her daughter is having twins.

The 38-year-old performer has spoken frequently about her desire to have kids.

Anthony --  a veteran performer and a megastar in his native Puerto Rico -- has received raves so far on the tour.

He will likely perform a mostly Spanish-language set.

Lopez, meanwhile, is expected to sing her own hits, including "Jenny From The Block'' and "Waiting for Tonight.''

A recent show ended with the couple performing together, kissing and nuzzling for the crowd.