Utilization of Imaging in Pregnant Patients: 10-year Review of 5270 Examinations in 3285 Patients—1997–2006

PURPOSE: To document the utilization of radiologic imaging in pregnant patients at one academic institution during a 10-year period (1997-2006). MATERIALS AND METHODS: The study was approved by the hospital institutional review board and was compliant with HIPAA. Informed consent was waived. At the authors' institution, pregnant patients exposed to radiation during imaging are recorded in a database compiled by the medical physics department. The authors retrospectively reviewed this database to document the number of patients, number of each type of imaging examination, date of the examination, and the estimated radiation dose to the fetus from 1997 to 2006. The authors searched the institution's medical records to obtain the total number of deliveries by year as a control for the total pregnant patient population. RESULTS: During the 10-year period, 5270 examinations were performed in 3285 pregnant patients (mean age, 28 years). The number of patients and examinations increased from 237 patients undergoing 331 studies in 1997 to 449 patients undergoing 732 examinations in 2006, an increase of 89% in patients and 121% in examinations. The total number of pregnant patients measured by deliveries increased 7%--from 8661 in 1997 to 9264 in 2006. Utilization rates (examinations per 1000 deliveries) of all radiologic examinations increased 107% from 1997 to 2006. The number of conventional radiographic examinations increased by an average of 7% per year, nuclear medicine examinations by 12% per year, and computed tomographic (CT) examinations by 25% per year. The average estimated fetal radiation exposure per examination was 0.43 mGy (range, 0.01-22.5 mGy) for conventional radiography, 4.3 mGy (range, 0.01-43.9 mGy) for CT, and 0.40 mGy (range, 0.01-7.7 mGy) for nuclear medicine examinations. CONCLUSION: For the comparison of 1997 to 2006, the radiologic utilization rate in pregnant patients increased by 107% from 1997 to 2006. The greatest increase was in CT.