Gastrointestinal (GI) endoscopy is a diagnostic and therapeutic procedure that allows imaging, assessing, and treating GI illnesses. Careful review of the available literature allows identification of important gender differences associated with the indications, performance, outcome, and risks for GI endoscopy. This chapter presents an overview of endoscopic techniques, examines current data regarding gender differences related to each major endoscopic procedure, and highlights specific issues pertaining to the performance of endoscopy in a pregnant patient. Women may be less tolerant to both sedated and unsedated colonoscopy and are more likely to describe colonoscopy as painful or uncomfortable. Women may be less satisfied with conscious sedation than men, although firm conclusions cannot be reached due to the limited amount of data available. Patient tolerance of both sedated and unsedated upper endoscopy (EGD) has been assessed. There are no major gender differences in tolerability, technique, or equipment use during endoscopic retrograde cholangiopancreatography (ERCP). Only highly trained personnel should perform ERCP during pregnancy, and its use should be limited to the treatment of threatening medical conditions including cholelithiasis complicated by jaundice, impacted choledocholithiasis, pancreatitis, or cholangitis. The reason that endoscopic ultrasound (EUS) does not expose the fetus to ionizing radiation, it may have an important role in the management of biliary, gallbladder disease, and cancer staging during pregnancy.