2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156931We find the conditions under which a quantum regression theorem can be assumed valid for non-Markovian master equations consisting in Lindblad superoperators with memory kernels. Our considerations are based on a generalized Born-Markov approximation, which allows us to obtain our results from an underlying Hamiltonian description. We demonstrate that a non-Markovian quantum regression theorem can only be granted in a stationary regime if the dynamics satisfies a quantum detailed balance condition. As an example we study the correlations of a two level system embedded in a complex structured reservoir and driven by an external coherent field.14 pages, 5 figures. Extended version. The GBMA is deduced from projector technique. A new appendix is addedQuantum Physicstext