The invention relates to a method for detecting a slow leak in an implantable hydraulic occlusive system in the human or animal body to occlude a natural conduit (10), said occlusive system comprising: - a hydraulic circuit comprising: - an inflatable occlusive cuff (9) containing a variable volume of a fluid, surrounding a portion of the natural conduit (10) to occlude, - a reservoir (4) containing a fluid, and - a fluidic connection (8) between the sleeve (9) and the reservoir (4), - an actuating device (2) coupled to a movable element of said hydraulic circuit and adapted to move said movable element to transfer a determined volume of fluid from the reservoir (4) to the sleeve (9) or the cuff to the reservoir, so as to vary the compression exerted by said sleeve (9) on said conduit (10), - a control unit (7) adapted to urge the actuating device (2) so as to exert a compre ssion determined on the conduit (10), the variation of the compression exerted by the sleeve on the conduit (10) being achieved by transfer of an adjustable volume of said fluid between the reservoir (4) and the sleeve (9), said method comprising: - measuring the evolution of the pressure in the hydraulic circuit for a determined load of the actuating device (2), said determined stress being a position of the movable element (22) defining a determined volume of fluid to transfer, - the detection of a slow leak in the hydraulic circuit when the pressure measured in said circuit for said determined solicitation of the actuating device (2) fulfills a predetermined criterion.L'invention concerne un procédé de détection d'une fuite lente dans un système occlusif hydraulique implantable dans le corps humain ou animal pour occlure un conduit naturel (10), ledit système occlusif comprenant : - un circuit hydraulique comprenant : - une manchette occlusive gonflable (9) contenant un volume variable d'un fluide, entourant une partie du conduit naturel (10) à occlure, - un réservoir (4) contenant un fluide,
