Evaluation of the effect of castor oil on initiating labor in term pregnancy.

OBJECTIVE: To determine the effect of castor oil on initiating labor in term pregnant women. METHODS: We conducted this randomized control clinical trial on 47 pregnant women from August 2003 to March 2004 in Mashhad University of Medical Sciences, Iran. RESULTS: There was a significant increase in labor initiation ratio in the castor oil group compared with the control group (54.2% compared with 4.3%, p<0.001). Also, the mean bishop score in the castor oil group increased from 2.50 +/- 1.29 to 6.79 +/- 3.20 (p<0.001). CONCLUSION: The probability of labor initiation increases during the first 24 hours after using castor oil, however, further studies are recommended to improve its efficacy and safety.