2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/35638A no-go theorem pertaining to the graceful exit problem in Pre-Big-Bang inflation is reviewed. It is shown that dilaton self-interactions and string fluid sources fail to facilitate branch changing necessary to avoid singularities. A comment on the failure of the higher genus corrections to induce graceful exit is also included.7 pages, latex, no figures, contributed talk at the 6th Canadian Conference on General Relativity and Relativistic Astrophysics, University of New Brunswick, Fredericton, NB, May 24-28General Relativity and Quantum Cosmologytext