The disclosure relates to a bra comprising two cups for accomodating the breasts of a user in which each cup is constituted by a piece of extensible textile material in the form of a substantially planar sheet when the bra is not worm, wherein a major part of the surface of the sheet is cut along a plurality of notches with a limited length arranged all around an inner part of the sheet in such a manner as to form a reversibly deformable structure suitable for being deployed to the front in a direction substantially transversal to the plane of the sheet under the effect of the weight of the breasts when the bra is being worn, causing this sheet to assume a volume conforming to the shape of the breasts and capable of supporting the breasts.