Evening primrose oil?

So I’m 35 weeks and I’ve been hearing a lot about it helping thin the cervix but no one is saying whether or not they used it orally or inserted it vaginay or if they broke it open and used the oil for perineal massage? **not looking to “induce labor” just trying to help in any way that I can to prepare my body for whenever the baby decides to come**

I should also mention I’m shooting to have a VBAC and that’s why I’m trying to prep my body in every way I can for a smooth natural onset of labor *hopefully*😂