A study of the influence of oxide apertures on the internal loss in vertical-cavity surface-emitting lasers (VCSEL's) is performed for two different aperture placements within the VCSEL cavity. It is found that when apertures are placed at a node in the standing wave of a VCSEL cavity there are negligible aperture dependent losses, However, when apertures are placed at an antinode there is a clear relationship between aperture dimension and internal loss.