Inflammatory bowel diseases are idiopathic, inflammatory, crohnic diseases of gastrointestinal tract with unpredictable course. Inflammatory bowel diseases include Crohn's disease and ulcerative colitis. Inflammatory bowel diseases often affect young women of reproductive age. The appearance of inflammatory bowel disease in pregnancy is equal to the incidence of these diseases in the general population. The disease can occur in pregnancy for the first time or as a relapse of an earlier known disease. In approximately 50% of patients younger than 35 Crohn’s disease occurs at the time of first diagnosis, and 25% become pregnant for the first time after diagnosis. A third of women with inactive Crohn's disease at conception will experience a relapse during pregnancy or puerperium. The disease presents clinically as intestinal perforation or obstruction. Diagnosis includes detailed history and use of modern time diagnostics such as colonoscopy, sigmoidoscopy and ultrasound. Treatment of Crohn's disease can be medical or surgical. Most often used drugs are infliximab and 5-aminosalicylic acid. The most common surgical procedure is resection of the intestine with anastomosis or stoma. Childbirth can be an elective vaginal or Cesarean section, and sometimes because of complications emergency C-section is done. Ulcerative colitis has a similar incidence in pregnancy as Crohn's disease. Diagnosis includes detailed medical history and ultrasound. Treatment is usually surgical Turnbull '' Blowhole '' surgery and a total abdominal colectomy. Childbirth is mostly elective or Caesarean section. The outcome of pregnancy in inflammatory bowel diseases is very good with occasional increased risk of premature infants, reduced body weight and height for gestational age.