Castor oil for induction of labor in post-date pregnancies: A randomized controlled trial – PubMed (nih.gov) Israeli article This effect was not noted among primiparous women. No differences in rate of obstetric complications or adverse neonatal outcomes were noted.

A study published in the journal Women and Birth (April, 2018) concluded:

“Nearly 91% of women in the study who consumed the castor oil cocktail to induce labor were able to give birth vaginally with little to no maternal or fetal complications.”