It is not supposed to bring on labor, and it won't, just so you know.
I started taking it orally at 35 weeks, and then inserting vaginally at 38 weeks.
When I went into labor on my due date, my cervix was fully effaced, which is what EPO is supposed to do, so I'd say it worked pretty well.
You could try inserting vaginally right now, but it takes a while to work, so unless you do a couple weeks overdue there probably isn't a point. But, it can't hurt!
Started taking it by mouth at 35 weeks, and vaginally at 37.
Did absolutely nothing for me. My cervix was closed and thick the day of my scheduled induction at 39 weeks.
but it won't hurt anything either, so feel free to give it try.
Best of luck.