The pictures from the raunchy shoot were taken when Heidi was three months pregnant yet her super-slim bod could be mistaken for that of a 20-year-old (even after three kids).
The soon-to-be mum of four posed in an unzipped dress, showing a glimpse of her pert derriere and then bares slightly more in a revealing snakeskin minidress.
The 36-year-old model has recently been seen sporting a glowing complexion and large baby bump with her husband Seal at the Los Angeles premiere and conference of Get Schooled.
Heidi's baby number four, which is expected next month, will join Leni, five, Henry, four, and Johan two.
By Georgie Hindle