Abstract: Intra-uterine system for inserting an active substance in an uterus, wherein the system comprises two flexible arms that extend from a central part in essentially mutually opposed directions, and retention means for the active substance, wherein during use the system is entered into the uterus, wherein an elongated housing extends from the central part at essentially equal angles with the flexible arms, wherein the housing comprises a storage container as retention means for the active substance, an outlet opening, a pump system, a control unit for controlled pumping of the active substance from the storage container through the outlet opening into the uterus and a energy storage means for supplying energy to the pump system and to the control unit.