I have been inserting for a week. I am barely dilated but my Dr said my cervix is very soft so should make for an easier labor but I'm 38 +5 and having to be induced this week. it only helps prep the cervix for labor but does start labor.
It just softens your cervix. If your body is ready to go into labor it can help speed things up, but if not it doesn't do anything.
I inserted 4 vaginally and lost my mucus plug the next morning...