Is it mandatory to get a prenatal gestational diabetes test?

No one in my family has diabetes, except for a distant cousin. My husband and I are both very adamant about NOT getting it done, because I'll never be able to keep the glucose drink down long enough, because while I don't have diabetes, I do have a very touchy stomach. I'll puke before I get a sip down and be sick the rest of the day, to the point where I'll probably have to get IV fluids for dehydration. (It has happened earlier in the pregnancy a few times already!) So, we want to avoid that if possible.