For measuring functionality of an orifice (16, 20) in the human pelvic region an elongated probe (4; 54) for insertion in the orifice (16, 20) is provided. The probe (4; 54) comprises one or more electrodes (5a-6a, 5b-6b, 6a-7a, 6b-7b; 55a-56a, 55b-56b, 56a-57a, 56b-57b, 57a-92a, 57b-92b) for stimulating receptors (23, 25) in tissue bounding the orifice (16, 20) and one or more muscle activity sensors (8a, 8b, 8c, 9a, 9b, 9c, 10a, 10b, 10c, 10d, 11a, 11b, 11e, 12a, 12b, 12c; 58a, 58b, 58c, 59a, 59b, 59c, 60a, 60b, 60c, 60d, 61a, 61b, 61c, 62) for sensing muscle activity causing pressure to be exerted by tissue bounding the orifice (16, 20). A control system (I) connected to the probe (4; 54) is arranged for outputting a neurostimulation signal (35) to the electrode or electrodes and for registering a pressure signal or signals from the pressure sensor or sensors during a time interval directly subsequent to the outputting of the neurostimulation signal.