The invention relates to a percutaneous gastrostomy probe with a tube (1), an internal retainer means (2) and an external collar (3). Said probe is substantially characterised in that the internal retention means (2) is made up of a) a collar (21), arranged against the stomach wall (4), which may be separated from the tube (1) by simply pulling, made from a non-biodegradable material selected only for the elastomeric properties thereof, b) an end piece (22), arranged against the external face of said collar (21), designed to maintain the same against the stomach wall (4), made from an entirely biodegradable polymer or copolymer the connection of which to the tube (1) has a pull apart rupture threshold as a function of the time for formation of the stoma.