There are several classes of biologics used to treat IBD.   Anti-TNF, anti-IL-12/23, anti-integrins.  These are all monoclonal antibodies that cross the placenta in the 2nd half of pregnancy. Previously, before the safety of these medications was understood physicians would administer the last dose of biologics before the third trimester, to minimize fetal exposure to the medication. However, women with IBD who require a biologic during pregnancy may continue the medications if the risks of having uncontrolled IBD outweigh the risks of fetal exposure

For more information regarding biologics in pregnancy, please go to our IBD Medications and Pregnancy Resources page.