From the Guidelines
CT scans of the abdomen and pelvis should be avoided during pregnancy unless absolutely necessary, due to radiation exposure risks to the developing fetus, but may be recommended in life-threatening situations for the mother or fetus. When considering diagnostic imaging during pregnancy, medical professionals follow the ALARA principle (As Low As Reasonably Achievable) to minimize radiation exposure. According to the American College of Radiology Appropriateness Criteria 1, CT of the abdomen and pelvis with IV contrast may still be recommended when there is a life-threatening concern for the mother or fetus. Some key points to consider include:
- The radiation dose from a typical abdominal/pelvic CT scan ranges from 10-35 mGy, which remains below the threshold of 50 mGy where fetal risks become more concerning 1.
- Alternative radiation-free options like ultrasound or MRI are typically preferred first, especially for evaluating causes of abdominal pain in pregnant women 1.
- In emergency situations where the mother's health is at serious risk and rapid diagnosis is crucial, the benefit of a CT scan may outweigh the potential risks.
- It is essential to inform medical staff about pregnancy or possible pregnancy before any imaging procedure and discuss concerns with a healthcare provider to determine the specific medical necessity and potential alternatives based on individual situations. The most recent guidelines from the American College of Radiology Appropriateness Criteria 1 emphasize the importance of weighing the benefits and risks of CT scans during pregnancy, and CT scans should only be used when the benefits outweigh the potential risks to the mother and fetus.
From the Research
Safety of CT Scan of the Abdomen and Pelvis during Pregnancy
- The use of CT scans during pregnancy is a topic of concern due to the potential risks of radiation exposure to the fetus 2, 3.
- However, in certain situations, such as suspected appendicitis or abdominal pain, a CT scan may be necessary to provide an accurate diagnosis 3.
- Studies have shown that CT scans can be useful in evaluating abdominal pain during pregnancy, especially when ultrasound or MRI results are inconclusive 2, 3.
- The American College of Radiology recommends that CT scans be used judiciously during pregnancy, with careful consideration of the potential benefits and risks 4.
Alternative Imaging Modalities
- Ultrasound is often the preferred initial imaging modality for evaluating abdominal pain during pregnancy due to its lack of ionizing radiation 5, 6.
- MRI is also a safe and effective imaging modality for evaluating abdominal pain during pregnancy, especially for diagnosing conditions such as appendicitis or ovarian torsion 5, 6.
- However, MRI may not always be available or feasible, and CT scans may be necessary in certain situations 2, 3.
Radiation Exposure and Fetal Risk
- The risk of radiation exposure to the fetus from a CT scan is a concern, especially during the early stages of pregnancy 2, 3.
- However, the benefits of an accurate diagnosis may outweigh the risks of radiation exposure in certain situations 3.
- Studies have shown that the use of CT scans during pregnancy can be justified in certain situations, such as suspected appendicitis, to reduce maternal and fetal mortality and morbidity 3.