MR imaging of maternal diseases of the abdomen and pelvis during pregnancy and the immediate postpartum period.

Magnetic resonance (MR) imaging provides multiplanar large field-of-view images of the body with excellent soft-tissue contrast and without ionizing radiation. As a result, MR imaging is increasingly being used to image the maternal abdomen and pelvis during and immediately after pregnancy. Results of rapid T1- and T2-weighted imaging are often diagnostic, and blood vessels, ductal structures, and the urinary tract can frequently be visualized without intravenous administration of contrast material. Until more conclusive safety data become available, MR imaging should be reserved for cases in which results of ultrasonography are inconclusive and patient care depends on further imaging. In the setting of acute abdomen during pregnancy, MR imaging allows identification of areas of inflammation, abscess formation, hemorrhage, and bowel obstruction. MR imaging also helps determine the organ of origin, extent, and composition of maternal neoplasms and is useful in evaluation of müllerian duct anomalies and abnormalities of placental formation, position, and implantation. Many postpartum complications such as retained products of conception and uterine dehiscence may be diagnosed with MR imaging when results of other modalities are indeterminate.