Tc-99m red blood cell bleeding scan in a pregnant woman presenting with hematemesis: a brief review of indications and guidelines for radionuclide scans during pregnancy.

A 6-month pregnant 35-year-old woman with hematemesis and dark blood in her stool was evaluated for location of an active gastrointestinal bleeding site. The findings from 2 esophagogastroduodenoscopies and a colonoscopy were negative. The patient was referred for a Tc-99m red blood cell scintigraphy, for location of an active bleeding site. As the patient was 6 months pregnant, the necessity of the case was discussed with the patient's referring physician and after determining that this study was necessary, the risk of radiation exposure to the fetus was discussed with the radiation safety officer and the patient. The procedure was performed after the patient signed informed consent regarding the considerations of radiation safety to the fetus. The Tc-99m red blood cell bleeding scan clearly shows activity in the fetus in addition to a large arteriovenous malformation in the patient. The visualized fetus prompted this report to discuss radiation risks concerns and a brief review of indications and guidelines for performing nuclear medicine procedures in pregnant patients.