This study is being done to determine whether the rates of birth defects, miscarriages, premature births and other outcomes in women with inflammatory bowel disease (IBD) taking azathioprine/6MP or biologic therapy or small molecules are different from those among IBD-affected women not taking these medications. Participants will be asked to give blood samples to assess drug levels during pregnancy and after birth. They will also be asked to answer questionnaires about their and their baby's health.