MRI can be indicated for use in pregnant women if other forms of diagnostic imaging are inadequate or require exposure to ionizing radiation such as X-ray or CT.
As a safety precaution, MR scanning should be avoided in the first three months of pregnancy.
Similar considerations hold for pregnant staff of a magnetic resonance department. An epidemiological study (by Kanal, et al.) concluded that data collected from MRI technologists were negative with respect to any statistically significant elevations in the rates of spontaneous abortion, infertility and premature delivery.
However, also for psychological reasons, it might be a wise precaution that pregnant staff members do not remain in the scan room during actual scanning.
There have been several reports (results could not be reproduced) that static magnetic fields may provoke genetic mutations, changes in growth rate and leukocyte count and other effects. No reports have been published that persons exposed to magnetic fields, including staff at MR departments, have a higher incidence of genetic damage to their children than found in the average population.
This research needs further investigation and for this purpose pregnancy should be considered a relative contraindication for MR spectroscopy and MRI procedures.
Taking into account that clinical MR imaging devices operate at field strengths of between 0.2 and 2.0 T, higher field strengths need more investigation.

Today, there is no sign that MR can harm the fetus or embryo (MRI is used for fetal MRI - fetography). However, if a MRI examination is ordered, there should be a strict indication for this examination.

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