# Magnesium sulfate before very preterm birth to protect the baby's brain Intervention · id `maternal:magnesium-sulfate-fetal-neuroprotection` · Maternal & Newborn Atlas · release `fc5a600ec7387e71` (public) > General information from published sources, not medical advice, and not reviewed by clinicians. Check the cited source before relying on anything here. The atlas's own text and curation may be reused under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0, https://creativecommons.org/licenses/by-nc/4.0/): credit the atlas, and do not use it commercially. See the atlas About page. Text quoted from a source stays under that source's own terms, given as the source's reuse\_basis. The atlas's reuse terms do not cover it. The downloads list each quotation with its source in third\_party\_quotations. Browse, life stage: Pregnancy; Newborn; Infant follow-up Browse, care area: Preterm and sick newborns ## In plain language Magnesium sulfate given by drip to a woman who is likely to give birth very early, in the hope of protecting the baby's brain. In the BEAM trial it did not lower the combined risk of death or moderate or severe cerebral palsy. Moderate or severe cerebral palsy alone was less common with magnesium sulfate, in a secondary analysis. This is a separate use from magnesium sulfate for eclampsia, and results for one use do not apply to the other. ## Technical summary Medicine strategy: the mother receives the medicine and cerebral palsy is measured in the child, so the claim context is mixed and a separate maternal context holds the one maternal result. The BEAM abstract gives the regimen (a 6-g bolus then 2 g per hour, intravenously) and population (women at imminent risk of delivery between 24 and 31 weeks); no other trial of this use is recorded in this atlas. Kept apart from the eclampsia record and linked to the magnesium sulfate drug page. ## Claims, with the population each applies to ## Context: Women at imminent risk of delivery at 24 to 31 weeks who received magnesium sulfate or placebo (BEAM trial) Recipient: Maternal; Population: The 2241 women randomised in BEAM, at imminent risk for delivery between 24 and 31 weeks of gestation. This context is for outcomes counted in the women; the abstract reports one: whether any woman had a life-threatening event.; Care setting: A multicentre, placebo-controlled, double-blind trial; the abstract names no wards; Geography: United States (ClinicalTrials.gov locations); Life stage: Pregnancy at 24 to 31 weeks with imminent delivery risk; Gestational age: 24 weeks 0 days (168 days) to 31 weeks 6 days (223 days), measured at enrolment; Postnatal age: Not reported; Follow-up: Maternal events during the trial; the abstract gives no other maternal outcomes. ### In BEAM, the abstract reports that no woman had a life-threatening event. - Category: Safety - Evidence stage: Interventional - Certainty: Certainty not assessed - Applies to: Recipient: Maternal; Population: The 2241 women randomised in BEAM, at imminent risk for delivery between 24 and 31 weeks of gestation. This context is for outcomes counted in the women; the abstract reports one: whether any woman had a life-threatening event.; Care setting: A multicentre, placebo-controlled, double-blind trial; the abstract names no wards; Geography: United States (ClinicalTrials.gov locations); Life stage: Pregnancy at 24 to 31 weeks with imminent delivery risk; Gestational age: 24 weeks 0 days (168 days) to 31 weeks 6 days (223 days), measured at enrolment; Postnatal age: Not reported; Follow-up: Maternal events during the trial; the abstract gives no other maternal outcomes. - Limitations: Only the abstract was read, and it reports this one maternal result with no number of women per group and no other maternal outcome (the registry lists maternal secondary outcomes, but their results were not read). It does not say that no woman had any side effect. - Last checked: 2026-10-15 - Sources: 1. Supports: A randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy (Publication, edition PubMed record (abstract and bibliographic data) from NCBI E-utilities. The full text and the version of record were not fetched.) Locator: Abstract, RESULTS sentence 7. Retrieved 2026-10-14T18:18:28Z. Source state: Current. Snapshot hash: 62ea8b7a65c13b5cc1b05f46b9c64c7a87f1d1be329c82c208ea044f0258b94d. How it applies: Maternal life-threatening events. 2. Background: A randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy (Publication, edition PubMed record (abstract and bibliographic data) from NCBI E-utilities. The full text and the version of record were not fetched.) Locator: Abstract, METHODS sentence 1 and RESULTS sentence 1. Retrieved 2026-10-14T18:18:28Z. Source state: Current. Snapshot hash: 62ea8b7a65c13b5cc1b05f46b9c64c7a87f1d1be329c82c208ea044f0258b94d. How it applies: Population and randomisation. ## Context: Women at imminent risk of delivery at 24 to 31 weeks, and their fetuses and children (BEAM trial) Recipient: Mixed recipients; Population: 2241 women at imminent risk of delivery between 24 and 31 weeks of gestation underwent randomisation; follow-up was achieved for 95.6% of the children. The registry's criteria add preterm labour with membrane rupture or planned delivery within 24 hours, and exclude women with hypertension or pre-eclampsia, among others. The medicine was given to the women; the primary outcome counts stillbirth and infant death together with moderate or severe cerebral palsy in the children, so the measured group is fetuses and children.; Care setting: A multicentre, placebo-controlled, double-blind trial; the abstract names no wards (the registry lists United States sites); Geography: United States (ClinicalTrials.gov locations); Life stage: Pregnancy at 24 to 31 weeks with imminent delivery risk; children followed to 1 year and to 2 years or more of corrected age; Gestational age: 24 weeks 0 days (168 days) to 31 weeks 6 days (223 days), measured at enrolment; Postnatal age: Not reported; Follow-up: Stillbirth or infant death by 1 year of corrected age, and moderate or severe cerebral palsy at or beyond 2 years of corrected age. ### In BEAM, 2241 women at imminent risk of delivery between 24 and 31 weeks of gestation were randomly assigned, in a placebo-controlled, double-blind trial, to intravenous magnesium sulfate (a 6-g bolus then 2 g per hour) or matching placebo. The primary outcome, a composite of stillbirth or infant death by 1 year of corrected age or moderate or severe cerebral palsy at or beyond 2 years of corrected age, was not significantly different: 11.3% with magnesium sulfate and 11.7% with placebo (relative risk 0.97; 95% CI 0.77 to 1.23). In a prespecified secondary analysis, moderate or severe cerebral palsy occurred significantly less often with magnesium sulfate (1.9% against 3.5%; relative risk 0.55; 95% CI 0.32 to 0.95). The risk of death did not differ significantly (9.5% against 8.5%; relative risk 1.12; 95% CI 0.85 to 1.47). Follow-up was achieved for 95.6% of the children. The authors conclude that fetal exposure did not reduce the combined risk of moderate or severe cerebral palsy or death, although the rate of cerebral palsy was reduced among survivors. - Category: Effect - Evidence stage: Interventional - Certainty: Certainty not assessed - Applies to: Recipient: Mixed recipients; Population: 2241 women at imminent risk of delivery between 24 and 31 weeks of gestation underwent randomisation; follow-up was achieved for 95.6% of the children. The registry's criteria add preterm labour with membrane rupture or planned delivery within 24 hours, and exclude women with hypertension or pre-eclampsia, among others. The medicine was given to the women; the primary outcome counts stillbirth and infant death together with moderate or severe cerebral palsy in the children, so the measured group is fetuses and children.; Care setting: A multicentre, placebo-controlled, double-blind trial; the abstract names no wards (the registry lists United States sites); Geography: United States (ClinicalTrials.gov locations); Life stage: Pregnancy at 24 to 31 weeks with imminent delivery risk; children followed to 1 year and to 2 years or more of corrected age; Gestational age: 24 weeks 0 days (168 days) to 31 weeks 6 days (223 days), measured at enrolment; Postnatal age: Not reported; Follow-up: Stillbirth or infant death by 1 year of corrected age, and moderate or severe cerebral palsy at or beyond 2 years of corrected age. - Limitations: Only the abstract was read. The trial's own primary outcome showed no benefit; the cerebral palsy result is a prespecified secondary analysis and the abstract gives no denominator for the cerebral palsy percentages. The composite counts stillbirths and infant deaths as well as cerebral palsy, which is why the context is mixed. The registry gives 2136 participants and the paper 2241 women randomised; the two are not reconciled here. This is magnesium sulfate given before early preterm birth for the baby's brain; it is a different use from eclampsia prevention and its evidence does not carry over. - Last checked: 2026-10-15 - Sources: 1. Supports: A randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy (Publication, edition PubMed record (abstract and bibliographic data) from NCBI E-utilities. The full text and the version of record were not fetched.) Locator: Abstract, RESULTS sentences 3 to 6 and CONCLUSIONS sentence 1. Retrieved 2026-10-14T18:18:28Z. Source state: Current. Snapshot hash: 62ea8b7a65c13b5cc1b05f46b9c64c7a87f1d1be329c82c208ea044f0258b94d. How it applies: Primary composite, cerebral palsy, death and the authors' conclusion. 2. Background: A randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy (Publication, edition PubMed record (abstract and bibliographic data) from NCBI E-utilities. The full text and the version of record were not fetched.) Locator: Abstract, BACKGROUND and METHODS, RESULTS sentence 1. Retrieved 2026-10-14T18:18:28Z. Source state: Current. Snapshot hash: 62ea8b7a65c13b5cc1b05f46b9c64c7a87f1d1be329c82c208ea044f0258b94d. How it applies: Population, dose, groups and primary outcome definition. ## Connected pages - BEAM: women at imminent risk of delivery at 24 to 31 weeks; death or cerebral palsy in the children: Preterm birth (`maternal:preterm-birth`) [a claim, not a settled fact; see claim `maternal:claim-beam-composite-and-cerebral-palsy` and its context] - Same medicine, different purpose and recipient (existing page): Magnesium sulfate to prevent and treat eclampsia (`maternal:magnesium-sulfate-eclampsia`) - The medicine used in this strategy (existing drug page): Magnesium sulfate (`maternal:magnesium-sulfate`) - Filed under this front: Medicines and vaccines (`maternal:front-medicines-and-vaccines`) - Investigated in: BEAM trial (antenatal magnesium sulfate and cerebral palsy) (`maternal:beam-trial`) ## Provenance Content hash: 5590575b48986a5488ec7cc04058e713644858a45d8f52d1af48d9c7df518911 Last substantive edit: 2026-10-15 Evidence last checked: 2026-10-15