I had one with DS1 and was in labour the next morning.

However, with DS3 i had one at 37 weeks, did nothing. Another at 39-40 weeks and i was already 3cms dialted, also did nothing. I went into labour at 9 days over.

Bub won't come until s/he is ready to come. I tried absolutely everything to get DS3 to come and nothing worked until i gave up trying.