Sorry, didn't see the "going into labor naturally" part before I voted. Here's my stats anyway though.

#1 - 41.5wks went into labor myself
#2 - 40wks exactly - AROM due to being 7cms after 4 months PTL (I think I would have gone that night anyway - was having ctx on the way to the hospital.)
#3 - 37wks - CNM stripped my membranes without permission - must have been ready though, since it worked?
#4 - 38wks - stripped again after being on bed rest for 6 wks - I was tired of ctx. It was really long and hard so I don't think I was ready. I was silly to agree to it - won't happen again!