The use of castor oil on cervical ripening in pregnancies

Background and The role of castor oil on cervical ripening is poorly understood and data in examining its efficacy within clinical trial are limited. This study was performed to evaluate the effect of utilizing castor oil on cervical ripening in pregnancies after 40 weeks. A randomized clinical trial study was performed on 200 pregnant women after 40 weeks in Shabikhany Hospital, in the City of Kashan, in 2004 to 2006. Women were divided to two groups (100 women in case group and 100 women in control group). Case group took 60 ml castor oil, while the control group omitted treatment. Comparison was then compared between the two groups for demographic characteristics: increase of Bishop Score, means of Bishop Score at entrance to study and 24 hours after entrance to study, onset of labor within 24 hours, method and time of delivery and newborns Apgar score by X2, followed by Fisher’s exact test, and paired-samples T and T-tests. Results showed that there were no significant differences in mother’s age, education, nationality, gravidity, gestational age, parity between two groups. Paired-sample T test showed significant difference between means of Bishop Score at entrance of study and 24 hours after entrance of study in case and control groups(p=0.00). Furthermore, the mean increase of Bishop score in the case group was 4.5±3.63 versus 0.67±1.25 in the control group during the 24 hour period. During 24 hours after entrance to study, uterine contraction occurred in 70% women in case and 12% women in control groups. Statistical test showed significant difference between the two groups and an increase of Bishop Score at the onset of uterine contractions (P<0.001). There were no significant differences in method of delivery and Apgar score in their newborns between the two groups. The results of this study showed that use of castor oil may lead to cervical ripening in pregnant women after 40 weeks, without increase in complication of pregnancy, such as caesarean, and decrease Apgar score.