About 25 weeks for me, I'm tall and DD was small for her age as well as low fluid. I had no belly. It was a bit disappointing, lol. At 34 weeks (when she was delivered), I only measured at about 25 weeks.
But, with this one, I'm 11+3 and I'm having to suck it in because we're not telling anyone til Christmas Day!! I can't wait to be able to see my parents and not suck it in!!

And PZ, your pregnancy photos are gorgeous! I looked at them the other day.