Impact of repetitive exposure to strong static magnetic fields on pregnancy and embryonic development of mice.

Purpose: To evaluate possible risks of strong static magnetic fields for embryo implantation, gestation, organogenesis, and embryonic development.

Materials And Methods: Pregnant mice were exposed for 75 minutes daily during the entire course of pregnancy at the bore entrance, representing the position of medical staff, and at the isocenter, representing the position of patients, of a 1.5 T and a 7 T human MRI scanner.

Repetitive exposure of mice to strong static magnetic fields in utero does not impair fertility in adulthood but may affect placental weight of offspring.

Purpose: To investigate the effect of daily exposure in utero to static magnetic fields during prenatal development on germ cell development and fertility of exposed offspring in adulthood.

Materials And Methods: Mice were exposed daily in utero to different static magnetic field strengths at the bore entrance or in the isocenter of 1.5 T and 7 T MRI systems during the entire course of prenatal development.

Repetitive exposure to a 7 Tesla static magnetic field of mice in utero does not cause alterations in basal emotional and cognitive behavior in adulthood.

In the past three decades, magnetic resonance imaging (MRI) has been increasingly used in obstetrics to aid diagnostics of maternal and fetal conditions and has generally been considered a safe imaging method. However, the development of higher-performance systems employing, for example, stronger fields to improve the technique's diagnostic potential, necessitates on-going safety evaluation. Rodent studies provide an excellent opportunity to investigate not only acute but also long-term effects of magnetic field exposure in a systematic manner, and a behavioral analysis might help to uncover subtler effects which might result from magnetic field exposure of the vulnerable developing brain.