Strange way to preform glucose test?

Alexah
I have a new Doctor with this pregnancy( my 3rd), and the way they do the glucose test is way different then the other ones I've done. They sent the drink home with me to drink 1 hour before I come into my appointment and then they do the blood draw. Ok that's fine, but I've always had a base blood draw before hand to check for low blood sugar as well as high blood sugar. And if a mother does have gestational diabetes, why would you have her pump herself full of sugar and then have her drive to the appointment?That doesn't seem safe. Maybe it's me but it doesn't make sense to me. Anyone else's Doctor do the glucose test this way?