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Neuroprotective effects of in utero exposure to magnesium sulfate

Hyagriv N Simhan, MD, MS
Katherine P Himes, MD, MSCR
Section Editor
Vincenzo Berghella, MD
Deputy Editor
Vanessa A Barss, MD, FACOG


Cerebral palsy is the leading cause of neurologic impairment in young children, and prematurity and low birth weight are the most important risk factors for developing the disease. (See "Epidemiology, etiology, and prevention of cerebral palsy".)

In utero exposure to magnesium sulfate before early preterm birth appears to decrease the incidence and severity of cerebral palsy. The use of magnesium sulfate for neuroprotection will be reviewed here. Use of magnesium sulfate for tocolysis or for seizure prevention in women with preeclampsia/eclampsia is discussed separately. (See "Inhibition of acute preterm labor", section on 'Magnesium sulfate' and "Preeclampsia: Management and prognosis", section on 'Regimen'.)


The mechanism for the neuroprotective effects of magnesium sulfate in preterm infants is not well understood. The following mechanisms have been proposed [1,2]:

Stabilization of cerebral circulation by stabilizing blood pressure and normalizing cerebral blood flow

Prevention of excitatory injury by stabilization of neuronal membranes and blockade of excitatory neurotransmitters, such as glutamate

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Literature review current through: Nov 2017. | This topic last updated: Nov 08, 2017.
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