The only reason I would say to refuse the u/s is if you feel your Dr. will become uneasy if there is a 'big baby' threat. I know you won't, and I know, YOU know that they are off, but a Dr. may not be as comforted in that thought, as most haven't read all the studies and research on it. So that's the only thing that sticks out as in, don't do the u/s.
As far as induction goes.....even at term and after 40 weeks, ACOG says NOT to induce just because a macrosomic baby is expected. So if they pull the big baby card, and say to induce, refuse it based on recommendations of the org. that sets the standard for their practice. I agree with you, 30 min of pushing for a first time mom, with a posterior baby is AMAZING, so you really won't have any trouble even if your baby is big, as baby size really doesn't have much to do with 'can she push the baby out' Fat is squishy, even in a 10lb baby.
I know it's hard to be happy when you are so uncomfortable. I really do feel for you. Maybe you could treat yourself to every week milestone, go get a massage, pedicure, spa day, whatever. When we hit 40 weeks (next Tuesday) I'm doing a pedi, (maybe slip in a mani without telling hubby

). At 41 weeks, I'm going prenatal massage! This way, you have something to look forward to every week.
Oh, and TOTALLY second the find something to do everyday so your not just sitting around pregnant. That's my problem. It's regularly 105 degrees here these coming weeks, so I'm kinda limited on activities

.
Oh, and drink lots of water to make sure you and baby are well hydrated in advance during the u/s to avoid the 'low fluid' stuff.
Much MUCH love to you!
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