This is a prospective, observational, multicenter registry, which will enrol pregnant women with IBD (CD, UC, or unclassified IBD) over 5 years in Spain. In addition, each incident gestation will be followed-up during pregnancy, and children born to those mothers will be followed-up over 4 years to determine the incidence of serious adverse events (such as alteration of developmental status, infections, neoplasia or any other serious adverse events) during the study period. In order to harmonize the inclusion of adverse events and complications, only serious adverse events will be registered . The main variable will be the development of serious infection in children as this is the outcome that had controversial results in previous studies.