Natural Course and Pathogenesis of Transient Focal Neurologic Symptoms During Pregnancy

Abstract

To determine the pathogenesis and course of transient focal neurologic symptoms in pregnant women and to identify prognostic variables that will enable targeted workup. Case-control series. Tertiary care university hospital. Pregnant patients with acute transient focal neurologic symptoms. Women with histories of migraine, recurrent thromboembolism, or cerebrovascular disease were excluded. Diffusion-weighted imaging (DWI), perfusion-weighted imaging, fluid-attenuated inversion recovery (FLAIR) imaging, gradient-recalled echo imaging, and magnetic resonance venography (MRV) and angiography to determine the presence of brain ischemia and venous thrombosis. Patients underwent echocardiography, duplex ultrasonography, and a battery of hypercoagulability tests and were followed up a mean of 12 months after the event. Twenty-eight controls and 14 patients were enrolled from 23 773 pregnancies. Mean age was 31.2 (range, 24-41) years and mean gestational age at symptom onset was 28 (range, 17-44) weeks. No controls reported transient focal neurologic symptoms, migraine aura, or headache. Presenting symptoms included dysphasia (6 patients) and hemisensory (5) and hemimotor (7) syndrome. In 4 patients, these symptoms were preceded by scintillating scotoma; in 9 patients, focal symptoms were followed by a first-ever, throbbing, migraine-like headache. Only 1 patient had evidence of frank infarction on magnetic resonance imaging (MRI); 2 patients had single, small, hyperintense bright foci on FLAIR imaging without accompanying lesions on DWI, and 11 patients had normal MRI and MRV results. Echocardiography, carotid duplex ultrasonography, and hypercoagulability results were negative in all patients. None of the patients had ischemic events and 4 (29%) developed migraines with aura headaches during follow-up. Focal neurologic symptoms in healthy pregnant women are frequently preceded by aural visual phenomena and can usually be attributed to a first-ever migraine attack. Cerebral ischemia is less common than migraine and can be reliably diagnosed with MRI. Extensive evaluations to assess a putative hypercoagulable state and cardiocerebrovascular pathology may not be warranted in all such patients.