This is reversible after discontinuation of the medication. In other patients, the cause is not clear. The effect of Crohn's disease on the course of pregnancy is minimal. The rate of birth defects is not notably different than that of the general population. There is a mild increased risk of spontaneous abortion and premature delivery, especially if the disease was active at the time of conception.
Pregnancy has no consistent effect on the course of Crohn's disease.
Of those who are in remission when they become pregnant, most will remain free of disease activity throughout the pregnancy. Sulfasalazine and mesalamine are considered relatively safe for use in pregnancy, and their continued use is recommended. As well, in patients who require corticosteriods for control of their disease, it is generally accepted that the benefit of these medications outweigh any small risk of adverse effects. Methotrexate and cyclosporine are best avoided during pregnancy. Crohn's disease is not curable by either medical or surgical treatment.