Many young women with IBD worry whether or not it is safe to go on the contraceptive pill. A recent study from Boston Massachusett s examines the importance of oral contraceptives as a cause of IBD. 232,452 women were followed up for a number of years from 1976 to present day. 315 developed CD and 392 UC. Compared with those who had never used oral contraceptives, those who had were 2.82 times as likely to develop CD and 1.22 times as likely to develop UC.
Does this mean that it is not safe for those with IBD to take the pill? I am unconvinced by the findings of this paper. The results are not consistent with well established clinical facts for example, that smoking is very bad for CD, but less so for UC.(..although smoking is undeniably bad for one’s health and it should be avoided even if you have UC).. Smoking had no effect on the development of CD in this study, but did appear to be important in those developing UC. Furthermore, the authors suggest that female sex hormones may pose a problem in CD, but this is completely contrary to our knowledge, as CD usually gets much better in pregnancy when the levels of female sex hormones are much higher than those in women taking the pill.
Because there is an association which is statistically significant between two factors does not necessarily mean that one factor causes the other. It may mean that there is some third factor, as yet undiscovered, which leads to women taking the pill and which also independently increases the risk of CD. In any case, the increase risk is relatively small and I shall have no hesitation in allowing my patients to continue on the pill if they are already taking it, or to start it if they decide this is the best option for them.
(Khalili H et al GUT 2013 62 1153-59)
This article was first published on the original crohns.org.uk blog. Research has moved on since, so please check current advice with your IBD team.