Fetal MRI in the first trimester, no harm found!

bbFetal MRI has long been a useful adjunct to ultrasound in the evaluation of fetal pathology. Generally felt to be safe in the second and third trimesters, it is typically avoided in the first trimester due to the potential risk of harming organogenesis. In a landmark study recently reported in the Journal of American Medical Association, Canadian researchers examined the medical records of more than 1.4 million deliveries in Ontario, Canada, between 2003 and 2015, and found that exposure to MRI in the first trimester was not associated with an increased risk of harm to the fetus or in early childhood.  Ray and colleagues also looked at the risk of exposure to gadolinium-based contrast agents during MRI at any point in pregnancy and found that it was associated with rare adverse outcomes postnatally. This is an important study, particularly for practitioners at tertiary care pediatric health care centers where early diagnosis of fetal pathology may help guide therapy and affect management.  For further information, regarding MRI and contrast agents in pregnancy please refer to the following resources:

Association Between MRI Exposure During Pregnancy and Fetal and Childhood Outcomes. Ray JG, Vermeulen MJ, Bharatha A, Montanera WJ, Park AL. JAMA. 2016 Sep 6;316(9):952-61. http://jama.jamanetwork.com/article.aspx?articleid=2547756

ACR-SPR Practice Parameter for the Safe and Optimal Performance of Fetal Magnetic Resonance Imaging (MRI)


ACR Manual on Contrast Media


David M. Mirsky MD

Children’s Hospital Colorado

Aurora, CO

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