Kourtney Kardashian has said she's not pregnant with a fourth child.Taking to Instagram, the 40 year old, who shares children Mason, 10, Penelope, seven, and five year old Reign with ex Scott Disick, 36, shared a saucy snap of herself posing in front of a mirror.The reality star could be seen standing in a walk-in closet, wearing a burnt orange ribbed bodysuit with ruffled sleeves while her bare legs were crossed.