I'm a dog groomer, and when I bathe, I empty the dog's anal glands. It's really not hard to do (unless the dog is overweight or too thin). You may be able to teach yourself how to do it so that you don't have to have the vet do it for you. Or, instead of taking her to the vet, take her to a groomer -- they are more experienced with anal glands, it's cheaper, and you'll get a nice bath along with it.