Castor oil has been used since ancient Egyptian times to help start labor. If you're past your due date, friends, relatives, or midwives will likely suggest this age-old home remedy, among various others (such as going for a bumpy car ride, having sex, or eating an entire pineapple).
While an overdue pregnant woman may be so eager to deliver that she'll do or eat just about anything to get labor going, castor oil is probably among the least pleasant options to try. But does it work? Is it safe? This article will try to address some of these issues.
The Internet is full of stories of women who took castor oil and delivered a few hours later. You may even know a few women in "real life" who have successfully used castor oil to induce labor. However (and this is a big however), these stories don't prove that castor oil really works. It is quite possible that these women would have gone into labor anyway, or were even already in very early labor by the time they took the castor oil, especially considering the fact that women who are trying to induce labor are typically overdue anyway.
The only true way to tell if castor oil helps to put a woman into labor is to study it systematically. A few studies have tried to examine this issue. They took a group of women (typically at 40+ weeks of pregnancy) and assigned about half to receive castor oil and the other half to receive no castor oil. They used statistics to make sure the groups were not significantly different in many important ways, and then saw who gave birth earlier. These studies were typically done over months or years in order to have enough women in the studies.
In one small study involving 47 women, 54.2 percent of women given castor oil started labor within 24 hours, compared to only 4.3 percent who were not given castor oil. Another study of 103 women showed similar results, with 57.7 of those given castor oil going into labor within 24 hours, compared to just 4.2 percent of those not given castor oil. However, a much larger study of 612 women found no differences in time to birth between the two groups.
Taken all together, it appears the jury is still out on this one. More research is necessary to know for sure if castor oil truly is effective for inducing labor.