Fetal MRI

The Fetal MRI Program at Beaumont is a collaborative, multidisciplinary effort, conceived to provide expert diagnosis, counseling and management to some of the most challenging abnormalities that may affect the unborn baby. Over the past several years we have performed hundreds of fetal MRIs to help elucidate some of the most challenging problems that a baby may face before birth.

Our program is based on extensive collaboration between maternal-fetal medicine specialists, board certified radiologists with subspecialty training in pediatric radiology, neuroradiology and body imaging, genetic counselors, pediatric radiologists, neuroradiologists, neonatologists, and pediatric surgeons. In addition to providing the best possible diagnosis, our team provides a comprehensive management plan, including multi-disciplinary conferences where parents and referring physicians are provided a single and coordinated explanation of the abnormalities found and a management plan.

What is fetal MRI?

MRI is a non-invasive diagnostic test that uses a large magnet, pulses of radiofrequency waves, and a computer to create detailed images of organs and structures within your body, including a detailed image of your baby. Physicians use MRI to diagnose conditions that may not be adequately assessed using other imaging methods, such as X-ray, ultrasound and CT scan. MRI is safer than tests that use radiation (like X-ray and CT scan).

During pregnancy, fetal MRI can be used to provide information about the fetal brain, chest and abdomen that cannot be gathered from ultrasound alone. This information allows your doctor to better understand how various abnormalities may correlate with your child’s development during pregnancy and in the future. Standard test results are limited, so it can be very difficult to counsel parents who have a fetus with an abnormality, since outcomes of the same abnormality can vary widely. Fetal MRI enables abnormalities to be classified more thoroughly, which can give parents a more accurate picture of what to expect for their child, both neurologically and developmentally.

How is a fetal MRI performed?

The MRI machine is a large, tube-shaped machine that a patient enters for a short time while lying comfortably on an exam table.

Unlike X-rays and CT scans, the MRI does not use radiation. Here’s how the MRI works:

  • A magnetic field is created and pulses of radio waves are sent from a scanner.
  • The radio waves move the nuclei of the atoms in your body out of their normal position. (Your body is made of tiny bits of matter called atoms. At the center of each atom is a nucleus. Nuclei is the plural of nucleus.)
  • As the nuclei realign into proper position, they send out radio signals.
  • The signals are received by a computer that converts them into images of the baby.
  • A radiologist (a board certified physician who specializes in reading images) creates a report and sends the information to your physician.

There is a microphone in the scanner, so the mother can talk to the MRI technologist who is performing the scan. The scan usually takes 30 to 40 minutes.

Is fetal MRI safe?

The magnetic field and radio waves are believed to be safe, and no adverse effects on unborn babies have been reported with normal use.

Benefits of fetal MRI

Although ultrasound is the standard way to take images of your baby during pregnancy, it can be limited in some of the information it provides. MRI can sometimes give more information when an abnormality is detected. For instance, MRI shows excellent detail of the developing brain, and, in many cases, can provide more information about the severity of an abnormality. This can lead to more informed decision-making by doctors and expectant parents. Fetal MRI can also give you and your doctor a better idea of what to expect during the remainder of your pregnancy and after-birth, and what special treatment, if any, your baby may need.

Fetal MRI is usually performed after an anomaly is suspected by ultrasound in order to better characterize it, or in patients at increased risk for specific anomalies, such as

  • fetal brain
  • skull, face and neck
  • baby’s chest
  • more precise measurements of the baby’s lungs in case small lungs are suspected
  • other complex problems that are difficult to diagnose by ultrasound alone

Risks of fetal MRI

Fetal MRI has been performed for a number of years, and there are no known risks to the fetus. Fetal MRI uses magnetic and radio waves to capture images of the baby, and it does not use ionizing radiation like CT scans and X-rays. Additionally, no intravenous contrast material (dye), special medication, or sedation is needed to perform the exam. The MRI is not painful for you or your baby.

Because the developing baby is extremely small and difficult to image during the first trimester, fetal MRI is performed only in the second and third trimesters.