More than 6000 pregnant women each year have an indication that warrants a flexible sigmoidoscopy or colonoscopy. In addition to the potential complications inherent in the risk of sedation and the procedures themselves, the endoscopist who performs these procedures in pregnant women must be aware of the potential to do harm to the fetus. This article reviews the existing literature as it pertains to flexible sigmoidoscopies and colonoscopies performed during pregnancy, including indications and diagnostic usefulness, safety, use of medications, and therapeutic interventions.