The 36-year-old singer, who welcomed her first child with soccer player Gerard Pique in January, said it was hard to make her comeback on TV post pregnancy, reported Contactmusic.
"(Losing baby weight) is the only thing that's been a little stressful. I knew I had to come back here to do The Voice two months after I had delivered a baby. I didn't have my four months of maternity like every woman on earth has. I'm not trying to complain, but it's been a process full of challenges," she said.
"I think that our mothers and grandmothers weren't under the pressure women of today are after delivering a baby. My dad says there's nothing better than meat over the bones. So he likes my mom a little chubby. She was never under the pressure to have to get to her old weight - and she never did.