Does the Contraceptive Pill Cause IBD?

In years past, women who may be at risk for inflammatory bowel disease (IBD) were counseled against taking an oral contraceptive pill ("the pill") because of the effect it may have on the risk of IBD. In particular, there were some studies that showed that women who use the pill may be at increased risk of developing Crohn's disease.

The jury is still out on whether or not the pill can be a trigger for IBD or for an IBD flare-up. For women who have IBD, contraception is an important topic, and there are only so many choices. Pregnancy in women with IBD should be planned in advance, and for many women, the pill is an affordable, effective, and readily available option to prevent pregnancy. Women at risk of IBD and who have IBD need to weigh their birth control choices carefully and talk with their doctors about how their health could be affected.

The Evidence Behind the Connection

The evidence on the connection between the pill and IBD is conflicting. There are some older studies that indicated there was a risk of developing IBD for women taking the pill, yet still, other studies that found there was no connection between the pill and IBD. The methods and results of some of these studies have since come into question, and the evidence linking IBD and the pill is generally considered to be weak.

One meta-analysis of 14 studies concluded that taking oral contraceptives may increase the risk of developing IBD, and especially Crohn's disease. Women who smoked cigarettes and took the pill for a long period of time were especially found to be at risk. There is some speculation that smoking and taking oral contraceptives work together to increase the risk of developing Crohn's disease. Crohn's disease is sometimes referred to as a "disease of smokers," and people with Crohn's disease are advised not to smoke because of the risk of a flare-up.

Another meta-analysis of 10 studies found that women who used the pill and already had IBD were not at an increased risk for having a flare-up. This study also found that women who had ulcerative colitis and were taking oral contraceptives had a similar concentration of hormones in their blood as healthy women. This would indicate that the women with ulcerative colitis from the two studies included in the analysis were able to absorb the pill as well as the healthy women.

A prospective cohort study of 117,375 women in the United States showed that women who take oral contraceptives and smoke are at an increased risk of ulcerative colitis. The risk of Crohn's disease was also increased in those who took oral contraceptives.

The Bottom Line

At this time, there isn't enough evidence to conclude one way or another that oral contraceptives can cause IBD. Most studies show that other factors (such as smoking) are also involved with the increased risk of IBD in women who take the pill. For women with IBD, pregnancy should be planned during a time when the IBD is in remission or quiescent. A pregnancy could also complicate recovery from abdominal surgery. Therefore, using contraceptives to prevent an unintended pregnancy during certain times in the course of IBD is important. For women with IBD, the potential side effects of oral contraceptives should be weighed against the risks of an unintended pregnancy.

Oral contraceptives are very popular because of their ease of use, their availability, and their effectiveness. For some women, other forms of birth control are not a good option because they are difficult to use or because they might not be used consistently. If you are at risk of IBD, or you have IBD, and you are considering the use of oral contraceptives, you should discuss any concerns you have with your gynecologist and your gastroenterologist. Your healthcare team can best help you determine the form of birth control that will be most effective for you.