The question is really whether IF something happens are you going to ve able to not attribute guilt to it?
Natural labour simulators will only work if baby is ready.
Nipple stimulation @ 37, 38 weeks, nothing.
Nipple stimulation at 39w4d, prelabour contractions and baby born 18 hours later.

No it doesn't bring it on, but it is always safer to not if you feel like you will feel guilty of something happens.