The onset of inflammatory bowel disease (IBD) usually occurs at young age, and therefore, women IBD patients experience pregnancy during their disease progression. Recently, the use of anti-tumor necrosis factor-α (anti-TNF-α) has been rapidly increasing. The aim of this study was to evaluate pregnancy related outcomes in women with IBD who were treated with anti-TNF-α during pregnancy and immunity of their children. Korean women with IBD who had been treated with anti-TNF-α during pregnancy had been enrolled. Medical records were reviewed and a survey was performed for each patient. For the patients who agreed on additional examination for their children, children's growth, medical history and antibody to hepatitis B surface antigen (anti-HBs) titer were checked. All 18 patients had been diagnosed with Crohn's disease. There was not any case of preterm delivery, low birth-weight infant, congenital anomaly, nor stillbirth. All 12 children had followed the regular vaccination schedule for hepatitis B and 4 of them showed negative results for anti-HBs. After the 1 booster vaccination, all children demonstrated seroconversion. Regarding live vaccines, 4 children had bacillus Calmette-Guerin and 4 had rotavirus vaccine before 6 months, without any specific side effects. This was the first study of immunity of the children born from IBD women who had been treated with anti-TNF-α medication during their pregnancy. IBD women had comparable pregnancy outcomes with the general women population, suggesting that the disease activity rather than the administered medication would be more important in healthy pregnancy. Considering the history of vaccination and anti-HBs titers, immunity seems to be intact in the children.