Nipple stimulation....safe in pregnancy???

Hey guys......i've been reading a lot of stuff about how nipple stimulation can bring on labour, i'm only 28 wks pregnant so obviously i'm not keen 2 hurry baby on JUST yet! The general opinion seems 2 b v mixed, some ppl saying its risky, others saying you'd have 2 b doing it 4 several hrs 4 it 2 have any effect, etc. Prob is its a regular part of foreplay between my partner and me and i'll b sorry 2 give it up (though i will of course if i have 2 as baby's safety is my main concern), and i intend 2 mention it on my nxt visit 2 my midwife, jst b sure, but i'm jst interested if anyone can shed any light on this? 😕