Evening primrose oil?

Has anyone used this to help labor go more smoothly? Did it work? And how did you use it vaginally or orally? Thinking about using it vaginally since I’m 40 +6 days and trying to do anything to get this baby to come on his own, going for a long walk today and was gonna pick up some EPo to insert tonight before bed. Anything else I should get at the store? I might get some red raspberry leaf tea as well and I don’t agree on the castor oil it’s too much of a risk for me. Any advice would help!