Process for the preparation of a an inverse latex comprising from 20% to 70% by weight and preferably from 25% to 50% by weight of a branched or crosslinked polyelectrolyte, characterized in that the said polyelectrolyte is a copolymer of 2- acrylamido-2-methylpropanesulfonic acid partially or totally salified with acrylamide and optionally one or more monomers chosen from monomers containing a partially or totally salified weak acid function and/or from neutral monomers other than acrylamide, said production process comprising the control of the pH in the initial aqueous phase; Cosmetic, dermopharmaceutical or pharmaceutical composition comprising the inverse latex directly obtained by said process.