I had round 1 of GTT last friday and I was told to go 2 hours without eating, then you go in and drink a 10 oz sugary drink, wait an hour, and they draw blood. I failed the first round so I had the 3 hour test on Monday and I'm waiting on my results. For the 3 hour test I had to fast- no food or drink for 12 hours- then go in, they drew blood, I drank the drink again, sat for an hour, had blood drawn, sat for an hour, had blood drawn, sat for an hour, and had the final blood drawn. It was absolutely no fun.