I didn't have sex for ages while I was in the late stages of my pregnancy and I went into labour naturally. my waters broke 11:45pm the night of my EDD. I went christmas shopping that day and I believe the walking and the HOT WEATHER while I was out and about helped alot. Or maybe it was just time. Bub will come when he/ashe is ready It's hard to be patient I know but it will all be over before you know it!
Goodluck!!!