Abstract: The balloon comprises at least two balloon sheets (1) sealed to one another along a peripheral edge (2) to form an inflatable body (4) and an inflatable stem (5) connected by its proximal end to the body. In order to be able to hold the balloon the stem comprises a handle portion (17) which has, in an uninflated flat state of the balloon, an inner width (w) comprised between 30 and 80 mm and a length of at least 80 mm. The stem (5) further comprises a proximal portion (18) which widens in such a manner towards the body (4) that, when holding the balloon in its inflated state upright by the handle portion (17), the body (4) of the balloon returns to one single stable position after having bent the balloon in a transverse direction. Since the balloon can be held by the inflated handle portion, no cups or sticks have to be attached to the balloon.