Safety of drug therapy for inflammatory bowel disease in pregnant and nursing women

Drug therapy is justified in pregnant patients with active inflammatory bowel disease. Selection of medical treatment depends on disease severity and the potential for fetal toxicity. Preferably, pregnancy should be planned to coincide with periods of disease quiescence, so that drug requirements can be minimized. Sulphasalazine and prednisolone are clearly safe in pregnancy and lactation. Preliminary studies suggest that low-to-moderate-dose mesalazine is well tolerated in pregnant and nursing mothers. Immunosuppressive therapy during pregnancy in transplant and nontransplant recipients may be associated with an increased risk of fetal growth retardation and prematurity. The risk of congenital malformations from azathioprine and cyclosporin is not markedly increased, although exposure to methotrexate during the first trimester may cause fetal loss and characteristic anomalies. Short-term therapy with metronidazole in the first trimester is not associated with an increased risk of teratogenicity, although the safety of this drug in pregnancy as primary therapy for Crohn's disease using higher doses for prolonged periods has not been confirmed.