I was measuring a week ahead 2 weeks ago and gained 5 lbs and now I'm measuring 3 weeks ahead.
I wasn't concerned as I'd been depressed about my house not selling and dh and I spent every day eating ice cream, drinking slushies and devouring other junk to make us happy...lol. Also haven't been moving as much because of the pelvic pain.
My midwife however, brought up the whole diabetes thing and told me if I was still going to refuse the test to at least lay off the sugar.
I googled (measuring ahead in third trimester) and I found an article saying that measurements at this stage are irrelevant so I'm going with that.