A urological medical device having a retrieval string is provided. The retrieval string has a proximal end connected the device and an opposed distal end. In a first embodiment, the retrieval string is configured in an initial confined form which, following a period of deployment in a patient's bladder, changes to an unconfined form in which the distal end of the retrieval string is extendible into the urethra to enable extraction of the device from bladder by pulling the retrieval string. The device may include a bioerodible component which permits the retrieval string to take the unconfined form following degradation of the bioerodible component in vivo. In another embodiment, the retrieval string includes a ferromagnetic material, which can be magnetically captured to facilitate removal of the device from the bladder. The ferromagnetic retrieval string may be buoyant in urine.
