  The no-boundary proposal is a theory of the initial conditions of the
universe formulated in semi-classical gravity, and relying on the existence of
regular (complex) solutions of the equations of motion. We show by explicit
computation that regular no-boundary solutions are modified, but not destroyed,
upon inclusion of expected quantum gravity corrections that involve higher
powers of the Riemann tensor as well as covariant derivatives thereof. We
illustrate our results with examples drawn from string theory. Our findings
provide a crucial self-consistency test of the no-boundary framework.
