Process for preparing a crosslinked gel of at least one polymer or one of its salts, comprising at least the steps that consist in: a) providing an aqueous medium containing at least one polymer, b) forming a homogeneous gel from the medium from step a), c) bringing the gel obtained in step b) into contact with an effective amount of at least one crosslinking agent d) crosslinking said mixture formed in step c) and e) recovering said crosslinked hydrogel, wherein at least said steps a) to d) are carried out within a hermetic cavity delimited at least partially by a deformable wall, the mixture present in the cavity being exposed, in step d), to conditions conducive to crosslinking.
