Sage oil... good or bad? does it work?

So I've heard that sage oil is really good to kick start labour. Having a few drops in the bath is supposed to help soften the cervix and send you into labour quite quickly. However after doing my own research online I can't decide if this is a bad idea or not? Some are saying it shouldn't be used as it causes painful labour and contractions are too strong/quick. some are saying only if you're overdue and some are saying it does work and helps ease labour and make less painful. Help! I'm 37 weeks and 3/5 engaged is it a good or bad idea?