Last week, a study published in JAMA Network Open revealed that increasing numbers of pregnant women in Canada and the US have been undergoing medical imaging over the past two decades. And the largest spikes, in particular, have been in MRI and CT scans.
Undergoing imaging studies while pregnant, however, could pose a significant health risk to one’s baby, leading to a variety of issues depending on the radiation dose and time of exposure, if applicable. Issues could include: developmental delays, congenital abnormalities, and perhaps even cancer.
“Several reviews have quantified the potential harm of radiation exposure in pregnant women and concluded that exposure to radiation from medical imaging should be carefully considered while weighing risks and benefits to the patient,” remarked the research team, which was led by UC Davis’s Diana Miglioretti and Kaiser Permanente Northern California’s Marilyn Kwan. “Notably,” they continued, “a CT scan of the maternal abdomen and pelvis delivers a dose of 15 to 21 mGy to the fetus, similar to doses associated with increased leukemia risk in children.”
One of the study’s goals was to assess the potential overuse of imaging in pregnant women and to quantify at what point radiation puts a fetus at risk. The study included 3.5 million pregnancies in 2.2 million women who birthed live babies after 24 or more weeks of gestation between January 1996 and December 2016 at six different healthcare systems in Ontario or the US. Imaging modalities undergone included nuclear medicine, angiography and fluoroscopy, CT, x-ray, and MRI.
The team found that on the whole, 3.6 percent in Ontario and 5.3 percent in the US underwent imaging studies that administered radiation. They speculated that the use of imaging in pregnant women could have rose over the study’s duration for a variety of reasons, such as patient or physician demand, medical uncertainty, defensive medical practices, or simply advances in medical technology. They noted, however, that the drastic increase in MRIs was a good sign, because those scans do not expose the mothers to radiation, and improve the likelihood of spotting fetal abnormalities.