ummm nup, never heard that one before! My feet are a 6 and I had a natural ... in fact a VBAC... as for bubs size, well I had midwives guess around 7 pound a few weeks out and he turned out to only be a little bub of 5 pound 12 1/2... so hmmmm have to be pretty good to get it right I think. With my first the reason he was c/s was due to him being breech bum first, so folded in half and they did and xray to measure my pelvis size before making recommendations, so wasn't guessed. Go for natural hun if you can, your body is designed for babies and your baby and body know what to do!!