Straight to the 3 hr glucose test

Sandy
My doctor office doesn't do the 1 hr test and everyone just does the 3 hr test. The doctor I had last time (who I will not be seeing again) was defensive about it when I questioned it and she said its based on research and is better for insurance and people's time, yadda yadda. 
Anyway, does anyone else have this going on? And does anyone know about this so called research and best practice? I didn't ask her because I'd already been there for 2 hrs and she was being super reactive and my toddler was ready to go.
I know I can request a different test but I'm just wondering if I should suck it up and just do the 3 hour one.