Vinegar was originally used on cloth diapers to “soften” them up and possibly as a disinfectant many years ago in the days of cotton and flannel flats and prefolds. However today’s cloth diapers do not need any further softening and with detergents that are effective and hot water settings, no additional disinfecting is needed either. Therefore vinegar in the wash is not needed and could even cause odor problems if any vinegar is left on the diapers. Vinegar’s acidic nature can also weaken the elastic used in diapers or covers when repeatedly used. It is not recommended by most cloth diaper manufacturers and may void any warranties.