Just wanted to crash and chime in here. I used Castor Oil with my last baby and it worked well.
I also wanted to add that the fact that there is correlation between meconium and castor oil is just that, a very weak correlation. There is no evidence that one causes the other. In fact, most moms who use Castor oil, tend to be overdue, which being overdue in and of itself increases the risk of passing Meconium. It's completely unproven that Castor oil has that effect.
Are they going to use the castor oil vaginally? They can give you a slow, stretching cervical massage with the castor oil. I have heard that is more successful than taking it orally. Castor oil taken orally stimulates the bowel muscles, which run paralell to the vaginal/uteran muscles, so in theory, all hte contractions of your bowels emptying stimulates contractions in the uteran muscles. But internally it has been shown to help dialation, like Cervadil.
Good luck! HTH.
Torre , Momma to Abrielle (4/07) and Annalise (7/09), Birthdoula, CNA, Aspiring Nurse, and wanna-be baby catcher. I ATE MY !