Neuroimaging During Pregnancy and the Postpartum Period.

New onset or exacerbation of preexisting neurologic symptoms during pregnancy often necessitates brain or spinal cord imaging. Magnetic resonance techniques are preferred imaging modalities during pregnancy and the postpartum period. Ionizing radiation with computed tomography and intravenous contrast material with magnetic resonance or computed tomography should be avoided during pregnancy. New onset of headaches in the last trimester or in the postpartum period may indicate cerebrovascular disease or a mass lesion, for which brain imaging is necessary. The continuum of cerebrovascular complications of pregnancy and enlarging lesions may produce neurologic symptoms later in pregnancy and after delivery, necessitating imaging.