BeyonceUPDATE: In an interview airing tomorrow, Beyonce's mother Tina Knowles tells talk show host Ellen Degeneres that the pregnancy rumors are "not true," TMZ is reporting.

PREVIOUSLY: Here we go again. Another round of rumors claiming Beyonce is pregnant with her first child are circulating online. Us Weekly's source claims the pregnancy came as a total surprise to B and her husband, rapper-mogul Jay-Z.

"B was shocked. She loves kids, but she wasn't ready to be a mother just yet ... She really wanted to get her album done and tour the world again," the source said.

Even record executive Kevin Liles, who has known Jay-Z for years, is speaking out about the couple. "Jay has been all about family since I met him, and he's always going to be," he said. "I wish them the best."

But is it true? In March, "rock solid sources" claimed B was expecting. But alas, Beyonce's publicist shot down the "untrue" rumor.