- About 1 in 5 US women has had imaging with ionizing radiation during pregnancy.
Why this matters
- Imaging studies are often important for diagnosing serious surgical conditions during pregnancy.
- However, they are often avoided or delayed because of concerns about potential fetal harm from ionizing radiation exposure.
- Overall, 5.3% of pregnant US women and 3.6% of Ontario women underwent imaging with ionizing radiation, 1996-2016.
- The percentage of pregnancies with imaging ranged from:
- CT: 0.4%-1.1%;
- MRI: 0.4%-1.4%;
- Conventional radiology: 3.1%-8.0%; and
- Angiography and fluoroscopy: 0.2%-0.5%.
- Racial disparities in imaging rates were noted (black women had higher rates compared with white women).
- US CT use rates increased from 2.0/1000 pregnancies in 1996 to 11.4/1000 in 2007 and then decreased to 9.3/1000 in 2016.
- The use of MRI is increasing compared with CT (2011-2016):
- US: 12.8 vs 10.6 per 1000.
- Ontario: 9.8 vs 6.2 per 1000.
- Retrospective cohort study.
- Cohort taken from 6 integrated health care systems in the United States and Canada (n=3,497,603).
- Main outcome was imaging rate per pregnancy.
- Funding: National Cancer Institute, Institute for Clinical Evaluative Sciences.
- Undercalculation possible because of repeat exams.