The present invention relates to a monitoring system (100) and method for use with a body of a subject. The system comprises a medical device (20), having a portion (28, 21) thereof configured to be placed inside the subject's body, said portion of the medical device being configured to be propelled by fluid pressure through a body lumen, at least two pressure sensors (40, 42, 45, 47) accommodated remotely from the subject's body at two different spaced-apart positions outside the subject's body and configured and operable to detect pressure at the two spaced-apart remote positions； said at least two pressure sensors being in fluid communication with at least one site inside the subject's body, a relation between the pressure at said at least one site and the pressures at said two spaced-apart remote positions being thereby indicative of the fluid pressure at said at least one site.
