A sphincter augmentation device includes a plurality of bodies and a flexible band coupled with the bodies. The bodies define a first circumferential portion of the device and are magnetically biased toward one another. The flexible band defines a second circumferential portion of the device such that the bodies are arranged non-axisymmetrically about a central axis of the device. The device is sized to be positioned around a human urethra so that the bodies and the flexible band bear inwardly against the urethra. The device is configured to transition between a radially expanded state and a radially contracted state by the magnetic bias of the bodies to constrict the urethra.