Raman spectroscopy has been used to study photosensitive effects in Ge-doped optical fibres. The spectrum obtained for a sample of the original fibre used by Hill et al is shown to have a large broadband fluorescence. A rapid photobleaching of a fluorescence band at 570nm has been observed in the photosensitive fibre. It is shown that the Ge(1) and Ge(2) defects have appropriate properties to produce a refractive index grating via a photobleaching process. A weak photosensitive production of SiH occurs in Ge-doped fibres subjected to 488nm, which have previously been subjected to hydrogen diffusion, the rate of production is found to be linear with the power squared.