Physicians' perceptions of teratogenic risk associated with radiography and CT during early pregnancy

OBJECTIVE. The objective of our study was to determine family physicians' and obstetricians' perceptions of the risk of major fetal malformations associated with exposure to radiation from radiography and CT during early pregnancy. MATERIALS AND METHODS. Structured questionnaires were sent to 400 family physicians and 100 obstetricians selected randomly across Ontario, Canada. The physicians were informed about the 1-3% baseline risk for major malformations and were asked about their perceptions of the risk to the fetus associated with an abdominal radiograph and an abdominal CT scan during early pregnancy and whether they would recommend a therapeutic abortion after such exposure. RESULTS. Fifty-five percent (218/400) of the family physicians and 69% (69/100) of the obstetricians responded to our questionnaire. Forty-four percent of family physicians estimated the risk associated with an abdominal radiograph to be 5% or greater, and 61% estimated the risk associated with an abdominal CT scan to be 5% or greater. Eleven percent of obstetricians estimated the risk associated with radiographs to be 5% or greater (P < 0.001), and 34% estimated the risk associated with CT scans to be 5% or greater (p < 0.001). Among family physicians, I % recommended an abortion if the fetus was exposed to radiation from radiography and 6% after exposure to radiation from CT. None of the obstetricians recommended an abortion after exposure to radiation from an abdominal radiograph, but 5% recommended an abortion after exposure to radiation from an abdominal CT scan in early pregnancy. CONCLUSION. Our survey shows that physicians who care for pregnant women perceive the teratogenic risk associated with an abdominal radiograph and an abdominal CT scan to be unrealistically high during early pregnancy. This misperception could lead to increased anxiety among pregnant women seeking counseling and to unnecessary terminations of otherwise wanted pregnancies. This perception of high teratogenic risk associated with radiation could also lead to a delay in needed care of pregnant women.