A number of people with inflammatory bowel disease start to develop the disease in their youth or even adolescence, and many of them will have to face the problem of having children in the future. Will inflammatory bowel disease affect their fertility? Will their disease be passed on to the next generation? Patients with inflammatory bowel disease should avoid “making babies” during the active phase of the disease. When the disease is under control and in remission, it is possible to prepare for pregnancy under the guidance of a doctor. Current research suggests that there is no difference in fertility rates between women with inflammatory bowel disease and normal women, but women with the disease should avoid conceiving during periods of active disease, as otherwise Crohn’s disease or ulcerative colitis may continue to progress or even worsen. Moreover, the risk of preterm delivery, stillbirth or spontaneous abortion is also higher when pregnancy occurs during the active period than in normal pregnant women. Even for male patients, they should try to avoid getting their spouses pregnant during the active phase because certain medications that may be taken during the active phase of inflammatory bowel disease, such as sulfonamides like lurasulfapyridine (sulfasalazine), can reduce the number of sperm production in men, although this side effect is reversible. It is important to mention that the effects of disease activity on the fetus are much greater than the effects of medications, and therefore, strict contraception should be used during periods of disease activity. Pregnancy planning in patients with inflammatory bowel disease is best scheduled during the remission phase of the disease. Determining whether the disease is in remission often requires a comprehensive evaluation of the disease, including clinical symptoms, such as the presence of mucus and blood in the stool, and normal hematologic tests (e.g., hematocrit, C-reactive protein). However, the most objective judgment is endoscopic and pathologic examination. When a patient plans to become pregnant, it is best to do so under the guidance of a physician. Conception should occur during the remission period (preferably after one year of inflammation control) and the maintenance of medication should be continued. Drugs commonly used to maintain disease in remission (e.g., salazosulfapyridine and 5-aminosalicylic acid) are safe for both mother and child, and no adverse effects on the fetus have been reported with the use of such drugs during pregnancy. Foreign sources generally agree that azathioprine can also be used during pregnancy, but methotrexate and thalidomide (reactive stop) are absolutely prohibited.