Re: Labor inducers?
EPO just does the same thing that semen does, it softens the cervix.
The Red Raspberry Leaf tea just strengthens your uterus, it should actually be used throughout your pregnancy to prepare for birth. and the castor oil (not to be confused with the oil that goes in the car) I have "heard" works just as well applied to the belly - rubbed in like a massage and then put on warm wet cloths to help it soak in. Avoids the extra effect of sitting on the pot all day.
However, Nothing works if your body isn't ready. And FWIW I was 4cm for over a month with my oldest and NOTHING worked, and believe me, I tried it all! (including the blue and black cohosh from the health food store)