Mum-to-be Christina Aguilera has followed in the footsteps of Demi Moore and Britney Spears - by provocatively stripping to reveal her bump on the cover of America's Marie Claire magazine. The Dirrty hitmaker proudly displays her bulging belly as she poses with nothing but a cropped leather jacket to hide her modesty - a trend started by Moore back in August 1991 when she appeared nude on the cover of Vanity Fair magazine, while a pregnant Spears bared all on the cover of Harper's Bazaar in June 2006. In the interview, Aguilera reveals that her pregnancy with husband Jordan Bratman had been planned - but that she never dreamed it would happen so soon. She says, "We were planning on starting to try after the (Back to Basics) tour (endsMay07). And so, I had gone off the (contraceptive) Pill to prepare my body, because I didn't know how much time it would take. "You've heard it takes some time - except with Power Egg and Super Sperm here. I'm like, 'Oh, my God, can you believe it just happened?'" Aguilera is expected to give birth to the couple's first child early next year (08).