I use EPO, orally, starting at 36 weeks and additionally, vaginally at 37 weeks. I also do accupuncture starting at 34 weeks. My daughter was born on her due date. You could wait until you're overdue, but many natural remedies take some time to work, so starting after 40 weeks is often too late. Assisting the cervix to ripen won't necessarily make you go into labour - it's just one piece of our bodies getting ready. Semen works like EPO, so lots of sex is helpful too.