The effect of a semiconductor microcavity on the radiative spontaneous recombination of an electron-hole pair strategically placed (by virtue of a quantum well) in the microcavity is considered. First-order perturbation theory is used in the quantum mechanical calculation of the spatially anistropic radiation rate and shows a strong influence of the cavity, and dipole position in the cavity, on the spontaneous photon emission process. Calculations are compared with previous experiments [T. J. Rogers, D. G. Deppe, and B. G. Streetman, Appl. Phys. Lett. 57, 1858 (1990)].