My first and second were both 40+10, and I am wondering what the chances of this baby being on about that same schedule are...
Timing of subsequent labors
#2 34w (induced for problems and OB didn't believe me on my dates..he felt I was really 38w, but baby despite being large, was indeed 34w and spend a month in the NICU)
#4/5 38w6d (twins)
#6 40w born on his due date!
I think if you've already had two 40+10....it's a pretty good bet, but as soon as you 'plan' for that, you'll have a baby earlier than that :)