An implant (in particular a stent) includes a main structure and a sensor assembly for measuring a body parameter. The sensor assembly includes at least one electrical conductor and at least one capacitor which are connected in such a way that the conductor and the capacitor form at least one electrical resonant circuit. The electrical conductor is surrounded by an electrical insulation. The electrical conductor is in the form of a coil having at least one turn. The capacitor is in contact at least on one side with the surrounding environment and its capacitance changes depending on the body parameter that is to be determined.