Magnetic resonance imaging involves using a highly powerful magnet to gather a series of images that are then projected on to a video screen. These images allow the health care provider to examine the various layers of the baby’s organ systems.
An MRI can be very useful in helping to estimate the size, volume, and maturity of fetal organs and for studying maternal and fetal anatomical structures. An MRI is a noninvasive type of technology in that no dyes or ionizing radiation is used.
MRIs are not widely available and, when they are available, they are costly to perform. Your doctor will only order an MRI is there is a specific medical reason for doing so. The FDA recommends against performing MRIs during the first trimester of pregnancy.
X-rays are rarely performed on pregnant women today and, when they are, they are generally only performed after the second trimester. Early prenatal exposure to radiation has been linked to leukemia and genetic mutations.