Oh and for DD I went 40 plus 4 (she was born 5 days over but began labour at 4 days over) and I went into spontaneous labour. It may have been purely coincidental but in the days prior I had been practising nipple stimulation, lots of walking and fit ball rolling/bouncing, happy endings as OP described them, and massage on my labour pressure points- inside wrists from memory, and inside ankles, or just above the inner ankles. But you should be able to Google it.