New research shows that women with inflammatory bowel disease (search) should continue to take medications that prevent flare ups of the disease during pregnancy.

About 1 million Americans suffer from inflammatory bowel disease -- usually ulcerative colitis (search) or Crohn’s disease (search). The conditions can be controlled with medications.

Flavio M. Habal, MD, PhD an associate professor in the division of gastroenterology, at the University of Toronto, in Ontario, Canada, tells WebMD that “the pregnancy outcome will be better -- for the woman and for the baby -- if she continues taking her medications. This is an important issue because many times obstetricians will advise women to stop all medications during pregnancy.”

Habal says that his study found “no birth defects associated with IBD medication use.”

Avoiding IBD Relapse

Habal and his colleagues followed 138 women with inflammatory bowel disease for 20 years to collect the data. Sixty of the women had ulcerative colitis and 76 had Crohn’s disease.

“During that time there were 174 births, so some of these women had multiple pregnancies.”

He says that women who stopped their medications during pregnancy were “more likely to have preterm delivery and small birth weight babies.”

The main concern with inflammatory bowel disease, says Habal, is to avoid a relapse, especially during pregnancy when a relapse is risky for both the woman and the fetus. He says that many women feel confident about stopping medications during pregnancy because “there is a belief that pregnancy by itself tends to reduce the risk of IBD relapse. Typically, women will say they feel great so they don’t need the medication.”

Harris Clearfield, MD, a professor at Drexel University College of Medicine in Philadelphia, tells WebMD that “pregnancy is a big issue with IBD since many of our patients become ill during the childbearing years. What usually happens is that the obstetrician will immediately advise the woman to stop all medications to protect the baby.”

Clearfield, who was not involved in the study, says “now that we have some evidence from this study we can share this information with obstetricians, because the real risk here is relapse. Nobody wants that to happen during pregnancy.”

But Habal says that the relapse rate for women off medication is no different during pregnancy. “So the risk for relapse does not decrease with pregnancy,” he says.

Fifty of the women stopped medications during pregnancy, while the rest continued on their regular drugs, which included oral 5-aminosalicylic acid, prednisone, and azathioprine. The pregnant women were compared with 83 nonpregnant women with IBD, and with 100 healthy pregnant women.

There were 32 inflammatory bowel disease relapses during 174 pregnancies, or about one in five pregnancies was complicated by a flare up of the disease. However, the researchers say this was no different from rates of flare ups in nonpregnant women. “The relapse rate for the nonpregnant IBD women was 22.9 percent, which is not significantly different,” says Habal.

However, when the researchers looked separately at women who continued their medications during pregnancy, flare ups occurred in approximately 10 percent, while women who stopped medications during pregnancy had a 34 percent relapse rate.

The birth weight of the babies born to mothers with inflammatory bowel disease was similar to the birth weight of babies born to the healthy mothers. But babies born to mothers who stopped IBD medications during pregnancy averaged only about 6.6 pounds, while women who continued medications gave birth to babies that averaged 7.3 pounds. “That difference was statistically significant,” says Habal.

By  Peggy Peck, reviewed by  Brunilda Nazario, MD

SOURCES: American College of Gastroenterology. Flavio M. Habal, MD, PhD, associate professor, division of gastroenterology, University of Toronto, Ontario, Canada.Harris Clearfield, MD, professor, Drexel University College of Medicine, Philadelphia.