In the years following pregnancy, a drop in the relapse rate is noted among women with inflammatory bowel disease (IBD), according to a recent report by European investigators.

However, narrowing or blockages of the bowel, also referred to as stenosis, and rates of bowel surgery did not seem to be affected by pregnancy.

Many studies have investigated the impact of IBD on pregnancy outcomes, but relatively few have looked at how pregnancy affects the course of IBD, lead author Dr. Lene Riis, from Herlev Hospital in Denmark, and colleagues note.

In their study, reported in the American Journal of Gastroenterology, the researchers assessed the IBD course in 266 patients who had become pregnant. The subjects included 173 with ulcerative colitis and 93 with Crohn’s disease.

Of the 580 pregnancies that occurred in the study group, 403 arose before IBD was diagnosed and 177 occurred afterward.

The spontaneous abortion rate was significantly higher in women with pre-existing IBD: 13 percent vs. 6.5 percent. The elective abortion rate, by contrast, was not affected by the timing of IBD and pregnancy.

The c-section rate was also higher in women with pre-existing IBD: 28.7 percent vs. 8.1 percent of pregnancies.

Among pregnant women with pre-existing disease, 48.6 percent took IBD medication at the time of conception and 46.9 percent took it during pregnancy.

As noted, pregnancy did not significantly influence the development of stenosis or the likelihood of bowel surgery. By contrast, relapse rates for ulcerative colitis and Crohn’s disease patients were significantly lower in the years following pregnancy compared with the period before conception.

Whether the reduction in flare-ups “is caused by the actual pregnancy or the intensive effort put into keeping the patient in remission remains unanswered,” the authors state. “A well-designed prospective study with long-term follow-up is needed in order to answer this question.”

SOURCE: American Journal of Gastroenterology, July 2006.