Association between the use of antenatal magnesium sulfate in preterm labor and adverse health outcomes in infants

Antenatal Low Dose Magnesium Sulphate for Foetal Neuroprotection in Preterm Birth Versus Control: A Comparative Prospective Cohort Study in Tertiary Care Centre in India

Introduction

Preterm infants are at great risk of neurological impairments. This study aimed to evaluate what is the difference in short- and long-term neonatal outcome comparing magnesium sulphate in small dose (4 g) versus controls.

Methods

Prospective cohort study was conducted in the Department of Obstetrics and Gynaecology over a period of 4 years. Group A comprised of the study group (intravenous 4 g magnesium sulphate was given over 20 min). Group B consisted of control group who did not receive magnesium sulphate.

Results

The study population comprised of 116 pregnant women who received intravenous bolus of 4 grams MgSO4 while the control group comprised of 95 pregnant women who did not receive MgSO4. Fewer neonates in the MgSO4 group required intubation at birth (32% vs. 52%) or chest compression (4% vs. 6%); however, the difference was not statistically significantly (p = 0.175 and p = 0.329). Neonatal brain ultrasound done in first month showed a significant reduction intraventricular haemorrhage of severe grade 3-4 IVH in the MgSO4 group (p = 0.016). MgSO4 administration was associated with a decrease in neonatal mortality before discharge (p = 0.039). Follow-up at 3 years showed a significant reduction in delayed milestones, visual impairment, Bayley score < 85 (p = 0.015). MgSO4 treatment antenatally was associated with lower risk of Cerebral Palsy (2.6% vs. 23.2%, p < 0.001).

Conclusion

The benefits from single smaller dose magnesium sulphate 4 gram prove its potential to be used for foetal neuroprotection in any healthcare setting without any maternal concerns.

Magnesium sulfate for fetal neuroprotection in preterm labor: an updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Antenatal magnesium sulfate has been reported to reduce the risk of neurological impairment in fetuses born to women at risk of preterm labor. However, the evidence to support its use is conflicting. We conducted this meta-analysis to assess the efficacy and safety of magnesium sulfate in women at risk of preterm labor as new research is available from RCTs giving insights into MgSO4 treatment among differing gestational age groups.

STUDY DESIGN

We searched various electronic databases, including MEDLINE (via PubMed), Embase, the Cochrane Library, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform portal from 1990 till 31st March 2024 to retrieve all randomized controlled trials (RCTs) that investigated the use of magnesium sulfate in women at risk of preterm labor with or without intent of fetal neuroprotection We used the revised Cochrane Risk of Bias tool (RoB 2.0) to assess the quality of the included randomized controlled trials. RevMan 5.4 was used to conduct all statistical analyses using a random-effects model. Our Meta-analysis was registered with the PROSPERO International Register of Systematic Reviews (CRD42024532421).

RESULTS

Our meta-analysis including eight RCTs showed that magnesium sulfate reduced the risk of cerebral palsy without a significant change in pediatric mortality. The change was evident in moderate to severe cerebral palsy. Magnesium sulfate showed no beneficial effect in most of the secondary outcomes.

CONCLUSIONS

This meta-analysis found antenatal magnesium sulfate reduces the risk of cerebral palsy with no difference in pediatric mortality between the magnesium or no magnesium treatment groups, which is a positive finding. However, there is still substantial heterogeneity between the studies, so there is a need for further exploration and discussion. The implications of this review include a concern for developing nations where resources and availability of magnesium sulfate are limited. Hence, further studies are needed to determine the exact dosage, timing, and whether maintenance dosage of magnesium sulfate is required or not and for how long.

Magnesium Sulfate Before Preterm Birth for Neuroprotection: An Updated Cochrane Systematic Review

OBJECTIVE

To systematically review the evidence for the effectiveness and safety of magnesium sulfate as a fetal neuroprotective agent when given to individuals at risk of preterm birth.

DATA SOURCES

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov , the World Health Organization International Clinical Trials Registry Platform (through March 17, 2023), and reference lists of relevant studies.

METHODS OF STUDY SELECTION

Randomized controlled trials (RCTs) assessing magnesium sulfate for fetal neuroprotection in pregnant participants at risk of imminent preterm birth were eligible. Two authors assessed RCTs for inclusion, extracted data, and evaluated risk of bias, trustworthiness, and evidence certainty (GRADE [Grading of Recommendations Assessment, Development and Evaluation]).

TABULATION, INTEGRATION, AND RESULTS

We included six RCTs (5,917 pregnant participants and 6,759 fetuses at less than 34 weeks of gestation at randomization). They were conducted in high-income countries (two in the United States, two across Australia and New Zealand, and one each in Denmark and France) and commenced between 1995 and 2018. Primary outcomes: up to 2 years of corrected age, magnesium sulfate compared with placebo reduced the risk of cerebral palsy (risk ratio [RR] 0.71, 95% CI, 0.57-0.89; six RCTs, 6,107 children) and death or cerebral palsy (RR 0.87, 95% CI, 0.77-0.98; six RCTs, 6,481 children) (high-certainty evidence). Magnesium sulfate had little or no effect on death up to 2 years of corrected age (moderate-certainty evidence) or these outcomes at school age (low-certainty evidence). Although there was little or no effect on death or cardiac or respiratory arrest for pregnant individuals (low-certainty evidence), magnesium sulfate increased adverse effects severe enough to stop treatment (RR 3.21, 95% CI, 1.88-5.48; three RCTs, 4,736 participants; moderate-certainty evidence). Secondary outcome: magnesium sulfate reduced the risk of severe neonatal intraventricular hemorrhage (moderate-certainty evidence).

CONCLUSION

Magnesium sulfate for preterm fetal neuroprotection reduces cerebral palsy and death or cerebral palsy for children. Further research is required on longer-term benefits and harms for children, effect variation by participant and treatment characteristics, and the generalizability of findings to low- and middle-income countries.

SYSTEMATIC REVIEW REGISTRATION

The review protocol was based on a standard Cochrane Pregnancy and Childbirth template and our previous Cochrane Systematic Review (doi: 10.1002/14651858.CD004661.pub3 ; published before the introduction of PROSPERO).

Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

BACKGROUND

Magnesium sulphate is a common therapy in perinatal care. Its benefits when given to women at risk of preterm birth for fetal neuroprotection (prevention of cerebral palsy for children) were shown in a 2009 Cochrane review. Internationally, use of magnesium sulphate for preterm cerebral palsy prevention is now recommended practice. As new randomised controlled trials (RCTs) and longer-term follow-up of prior RCTs have since been conducted, this review updates the previously published version.

OBJECTIVES

To assess the effectiveness and safety of magnesium sulphate as a fetal neuroprotective agent when given to women considered to be at risk of preterm birth.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 17 March 2023, as well as reference lists of retrieved studies.

SELECTION CRITERIA

We included RCTs and cluster-RCTs of women at risk of preterm birth that assessed prenatal magnesium sulphate for fetal neuroprotection compared with placebo or no treatment. All methods of administration (intravenous, intramuscular, and oral) were eligible. We did not include studies where magnesium sulphate was used with the primary aim of preterm labour tocolysis, or the prevention and/or treatment of eclampsia.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed RCTs for inclusion, extracted data, and assessed risk of bias and trustworthiness. Dichotomous data were presented as summary risk ratios (RR) with 95% confidence intervals (CI), and continuous data were presented as mean differences with 95% CI. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included six RCTs (5917 women and their 6759 fetuses alive at randomisation). All RCTs were conducted in high-income countries. The RCTs compared magnesium sulphate with placebo in women at risk of preterm birth at less than 34 weeks' gestation; however, treatment regimens and inclusion/exclusion criteria varied. Though the RCTs were at an overall low risk of bias, the certainty of evidence ranged from high to very low, due to concerns regarding study limitations, imprecision, and inconsistency. Primary outcomes for infants/children: Up to two years' corrected age, magnesium sulphate compared with placebo reduced cerebral palsy (RR 0.71, 95% CI 0.57 to 0.89; 6 RCTs, 6107 children; number needed to treat for additional beneficial outcome (NNTB) 60, 95% CI 41 to 158) and death or cerebral palsy (RR 0.87, 95% CI 0.77 to 0.98; 6 RCTs, 6481 children; NNTB 56, 95% CI 32 to 363) (both high-certainty evidence). Magnesium sulphate probably resulted in little to no difference in death (fetal, neonatal, or later) (RR 0.96, 95% CI 0.82 to 1.13; 6 RCTs, 6759 children); major neurodevelopmental disability (RR 1.09, 95% CI 0.83 to 1.44; 1 RCT, 987 children); or death or major neurodevelopmental disability (RR 0.95, 95% CI 0.85 to 1.07; 3 RCTs, 4279 children) (all moderate-certainty evidence). At early school age, magnesium sulphate may have resulted in little to no difference in death (fetal, neonatal, or later) (RR 0.82, 95% CI 0.66 to 1.02; 2 RCTs, 1758 children); cerebral palsy (RR 0.99, 95% CI 0.69 to 1.41; 2 RCTs, 1038 children); death or cerebral palsy (RR 0.90, 95% CI 0.67 to 1.20; 1 RCT, 503 children); and death or major neurodevelopmental disability (RR 0.81, 95% CI 0.59 to 1.12; 1 RCT, 503 children) (all low-certainty evidence). Magnesium sulphate may also have resulted in little to no difference in major neurodevelopmental disability, but the evidence is very uncertain (average RR 0.92, 95% CI 0.53 to 1.62; 2 RCTs, 940 children; very low-certainty evidence). Secondary outcomes for infants/children: Magnesium sulphate probably reduced severe intraventricular haemorrhage (grade 3 or 4) (RR 0.76, 95% CI 0.60 to 0.98; 5 RCTs, 5885 infants; NNTB 92, 95% CI 55 to 1102; moderate-certainty evidence) and may have resulted in little to no difference in chronic lung disease/bronchopulmonary dysplasia (average RR 0.92, 95% CI 0.77 to 1.10; 5 RCTs, 6689 infants; low-certainty evidence). Primary outcomes for women: Magnesium sulphate may have resulted in little or no difference in severe maternal outcomes potentially related to treatment (death, cardiac arrest, respiratory arrest) (RR 0.32, 95% CI 0.01 to 7.92; 4 RCTs, 5300 women; low-certainty evidence). However, magnesium sulphate probably increased maternal adverse effects severe enough to stop treatment (average RR 3.21, 95% CI 1.88 to 5.48; 3 RCTs, 4736 women; moderate-certainty evidence). Secondary outcomes for women: Magnesium sulphate probably resulted in little to no difference in caesarean section (RR 0.96, 95% CI 0.91 to 1.02; 5 RCTs, 5861 women) and postpartum haemorrhage (RR 0.94, 95% CI 0.80 to 1.09; 2 RCTs, 2495 women) (both moderate-certainty evidence). Breastfeeding at hospital discharge and women's views of treatment were not reported.

AUTHORS' CONCLUSIONS

The currently available evidence indicates that magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus, compared with placebo, reduces cerebral palsy, and death or cerebral palsy, in children up to two years' corrected age, and probably reduces severe intraventricular haemorrhage for infants. Magnesium sulphate may result in little to no difference in outcomes in children at school age. While magnesium sulphate may result in little to no difference in severe maternal outcomes (death, cardiac arrest, respiratory arrest), it probably increases maternal adverse effects severe enough to stop treatment. Further research is needed on the longer-term benefits and harms for children, into adolescence and adulthood. Additional studies to determine variation in effects by characteristics of women treated and magnesium sulphate regimens used, along with the generalisability of findings to low- and middle-income countries, should be considered.

Antenatal Magnesium Sulfate Is Not Associated With Improved Long-Term Neurodevelopment and Growth in Very Low Birth Weight Infants

BACKGROUND

Though antenatal magnesium sulfate (MgSO4) is widely used for fetal neuroprotection, suspicions about the long-term neuroprotection of antenatal MgSO4 have been raised.

METHODS

We investigated short- and long-term outcomes of antenatal MgSO4 use for 468 infants weighing < 1,500 g with a gestational age of 24-31 weeks.

RESULTS

Short-term morbidities and the risk of developmental delay, hearing loss, and cerebral palsy at a corrected age of 18-24 months and 3 years of age did not decrease in the MgSO4 group (infants who were exposed to MgSO4 for any purpose) or neuroprotection group (infants who were exposed to MgSO4 for fetal neuroprotection) compared with the control group (infants who were not exposed to MgSO4). The z-scores of weight, height, and head circumference did not increase in the MgSO4 group or neuroprotection group compared with the control group.

CONCLUSION

Antenatal MgSO4 including MgSO4 for neuroprotection did not have beneficial effects on long-term neurodevelopmental and growth outcomes.

Prenatal Intravenous Magnesium at 30-34 Weeks' Gestation and Neurodevelopmental Outcomes in Offspring: The MAGENTA Randomized Clinical Trial

Importance

Intravenous magnesium sulfate administered to pregnant individuals before birth at less than 30 weeks' gestation reduces the risk of death and cerebral palsy in their children. The effects at later gestational ages are unclear.

Objective

To determine whether administration of magnesium sulfate at 30 to 34 weeks' gestation reduces death or cerebral palsy at 2 years.

Design, Setting, and Participants

This randomized clinical trial enrolled pregnant individuals expected to deliver at 30 to 34 weeks' gestation and was conducted at 24 Australian and New Zealand hospitals between January 2012 and April 2018.

Intervention

Intravenous magnesium sulfate (4 g) was compared with placebo.

Main Outcomes and Measures

The primary outcome was death (stillbirth, death of a live-born infant before hospital discharge, or death after hospital discharge before 2 years' corrected age) or cerebral palsy (loss of motor function and abnormalities of muscle tone and power assessed by a pediatrician) at 2 years' corrected age. There were 36 secondary outcomes that assessed the health of the pregnant individual, infant, and child.

Results

Of the 1433 pregnant individuals enrolled (mean age, 30.6 [SD, 6.6] years; 46 [3.2%] self-identified as Aboriginal or Torres Strait Islander, 237 [16.5%] as Asian, 82 [5.7%] as Māori, 61 [4.3%] as Pacific, and 966 [67.4%] as White) and their 1679 infants, 1365 (81%) offspring (691 in the magnesium group and 674 in the placebo group) were included in the primary outcome analysis. Death or cerebral palsy at 2 years' corrected age was not significantly different between the magnesium and placebo groups (3.3% [23 of 691 children] vs 2.7% [18 of 674 children], respectively; risk difference, 0.61% [95% CI, -1.27% to 2.50%]; adjusted relative risk [RR], 1.19 [95% CI, 0.65 to 2.18]). Components of the primary outcome did not differ between groups. Neonates in the magnesium group were less likely to have respiratory distress syndrome vs the placebo group (34% [294 of 858] vs 41% [334 of 821], respectively; adjusted RR, 0.85 [95% CI, 0.76 to 0.95]) and chronic lung disease (5.6% [48 of 858] vs 8.2% [67 of 821]; adjusted RR, 0.69 [95% CI, 0.48 to 0.99]) during the birth hospitalization. No serious adverse events occurred; however, adverse events were more likely in pregnant individuals who received magnesium vs placebo (77% [531 of 690] vs 20% [136 of 667], respectively; adjusted RR, 3.76 [95% CI, 3.22 to 4.39]). Fewer pregnant individuals in the magnesium group had a cesarean delivery vs the placebo group (56% [406 of 729] vs 61% [427 of 704], respectively; adjusted RR, 0.91 [95% CI, 0.84 to 0.99]), although more in the magnesium group had a major postpartum hemorrhage (3.4% [25 of 729] vs 1.7% [12 of 704] in the placebo group; adjusted RR, 1.98 [95% CI, 1.01 to 3.91]).

Conclusions and Relevance

Administration of intravenous magnesium sulfate prior to preterm birth at 30 to 34 weeks' gestation did not improve child survival free of cerebral palsy at 2 years, although the study had limited power to detect small between-group differences.

Trial Registration

anzctr.org.au Identifier: ACTRN12611000491965.

School-Age Outcomes of Antenatal Magnesium Sulphate in Preterm Infants

BACKGROUND

Antenatal magnesium sulphate (MgSO4) therapy given to women at risk of preterm birth reduced the risk of cerebral palsy in early childhood. However, its effect on longer-term neurological outcomes remains uncertain. This study aimed to assess the effects of antenatal MgSO4 therapy on school-age outcomes of preterm infants.

METHODS

We conducted a systematic review and meta-analysis. We searched MEDLINE, EMBASE, CENTRAL, and CINAHL for randomized controlled trials (RCTs). Two reviewers independently evaluated the eligibility for inclusion and extracted data.

RESULTS

Ten RCTs were included. Only two of them were on school-age outcomes. Antenatal MgSO4 therapy had no impact on cerebral palsy, hearing impairment, neurosensory disability, and death at school-age. Meta-analysis on mental retardation and visual impairment was not able to be performed due to different methods of evaluation. In the analysis of short-term outcomes conducted as secondary outcomes, antenatal MgSO4 therapy increased the risk of maternal adverse events with any symptom (3 RCTs; risk ratio 2.79; 95% confidence interval 1.10 to 7.05, low certainty of evidence) but was not associated with any neonatal symptoms.

CONCLUSIONS

The number of cases was insufficient to determine the impact of antenatal MgSO4 therapy on school-age outcomes. Further accumulation of long-term data is required.

Does Antenatal MgSO 4 Administration to the Mother in the Event of Imminent Premature Birth Reduce the Occurrence of Infantile Cerebral Palsy in the Child? - An Umbrella Review

Introduction Premature births have a significantly increased risk of developing cerebral palsy. This clinical picture involves great restrictions and impairments in the lives of the children and their families. Its prevention is therefore of great importance. One method of neuroprotection to reduce the rate of infantile cerebral palsy is the antenatal administration of magnesium sulfate to the mother. The aim of this paper is to present the current state of research of existing reviews and meta-analyses on the topic and to review the evidence for this intervention. Material and Methods A literature search was conducted within the framework of an umbrella review in the electronic database PubMed in February 2022 to identify all relevant publications on the topic. The search was structured using the PRISMA statement. The important methodological characteristics and the results of the studies were then extracted. In addition, a quality assessment of the studies was performed using the AMSTAR score. Results Two systematic reviews with meta-analysis, one systematic review, and one individual participant data meta-analysis were included in this study. The total number of subjects was n = 6178. The publications conclude that the antenatal administration of magnesium sulfate to the mother significantly reduces the risk of cerebral palsy in preterm infants. Due to the high quality of 3 of the 4 studies, a high level of evidence can be assumed. Conclusion The evidence for antenatal magnesium sulfate administration for the prophylaxis of cerebral palsy in preterm infants is high. However, further research is needed to determine which doses of magnesium and up to which gestational age the administration is useful.

Some Immune Parameters of Term Newborns at Birth Are Associated with the Concentration of Iron, Copper and Magnesium in Maternal Serum

The nutritional status of pregnant women is considered to affect fetal development and the health condition of newborns, including their immune system. We investigated the relationship between the concentrations of magnesium (Mg), calcium (Ca), zinc (Zn), iron (Fe) and copper (Cu) in maternal serum (MS) and the concentrations of IgG antibodies and antineutrophil cytoplasmatic auto-antibodies against lactoferrin (Lf-ANCA) in umbilical cord serum (UCS). IgG was considered as a promoter of immunity, and Lf-ANCA as an inhibitor. The examined group consisted of 98 pregnant women and their healthy term newborn children. The concentrations of mineral elements were measured by FAAS/FAES, while the concentrations of antibodies were determined by ELISA. Excessive MS Fe and insufficient MS Cu were related to insufficient UCS IgG and excessive UCS Lf-ANCA. The correlation analysis showed confirming results. Adequate UCS IgG and Lf-ANCA were related to MS Mg at the strictly lower limit of the reference values. The results obtained seem to suggest that an excess of Fe and a deficiency of Cu in pregnancy may adversely affect some immune parameters of newborns. Reference values for MS Mg are likely to require reconsideration. It would be advisable to monitor the nutritional status of pregnant women with minerals in order to support the immune capacity of newborns.

Efficacy of Antenatal Magnesium Sulfate for Neuroprotection in Extreme Prematurity: A Comparative Observational Study

Background

Survival of preterm infants has improved drastically. In addition to significant contribution to neonatal mortality, impact of prematurity among survivors may continue through life impairing long-term physical life through neuro-disability and increased risk of cerebral palsy. Maternal administration of magnesium sulfate prior to impending preterm birth is an effective strategy to reduce neuromorbidity.

Aim

To investigate the effectiveness of antenatal magnesium sulfate for neuroprotection in preterm infants between 26 and 34 weeks in preventing early neonatal morbidity and mortality. Secondary objective was to assess any adverse events with the use of magnesium sulfate on the mother and neonate.

Method

This was a prospective observational comparative study for 2 years at our tertiary care hospital of 100 pregnant women who gave preterm births. Fifty infants each were born to mothers who were either not given MgSO4 (Group 1) or given 4gm intravenous loading dose MgSO4 (Group 2), preferably 4 h prior to preterm birth.

Results

Among all the preterm in our study, 81% delivered between 30 and 34 weeks. There was no significant difference in terms of maternal mortality or serious morbidity including postpartum hemorrhage, caesarian section rates or length of hospital stay among women receiving MgSO4 versus no MgSO4. Mild maternal side effects secondary to magnesium sulfate were experienced in 8% cases. There were no significant differences between both groups for low 5 min APGAR, need for NICU admission, neonatal convulsions, hyperbilirubinemia, necrotizing enterocolitis, periventricular leukomalacia and septicemia. There was a trend toward reduced risk in the magnesium sulfate group for need for mechanical ventilation and ongoing respiratory support, intraventricular hemorrhage, neonatal hypotension, hypothermia, length of NICU stay. IVH was less frequent and less severe in babies exposed to antenatal MgSO4 (8%) as compared to non-MgSO4 group (16%). Neonatal morbidities were more when antenatal MgSO4 was given less than 4 h from delivery.

Conclusion

MgSO4 is a safe drug to use in antenatal women at risk for impending preterm. Antenatal magnesium sulfate given to women in established preterm labor conferred significant neuroprotective advantage to the neonate. MgSO4 also has protective effect on the need of invasive ventilatory support in preterm infants. Given the breadth of evidence in its favor, it is time for us to start using MgSO4 in clinical practice for neuroprotective intent in all our extreme preterm births.

Antenatal Magnesium Sulfate for Preterm Neuroprotection: A Single-Center Experience from Kuwait Tertiary NICU

Objectives

The study aimed to evaluate the impact of antenatal exposure of magnesium sulfate (MgSO₄) on short- and long-term outcomes in preterm neonates born less than 32 weeks gestation.

Methods

Single-center retrospective cohort study of 229 neonates born between 24 and 32 weeks gestation was conducted from January 2018 through December 2018 in a level III neonatal care unit in Kuwait. Antenatal MgSO₄ exposure was collected from the medical records, and the indication was for neuroprotection effect. Brain MRI was done on 212 neonates (median gestational age 36 weeks), and brain injury was assessed using the Miller's score. Neurodevelopmental outcome was assessed by Bayley-III scales of infant development at 36 months corrected age (N = 146). The association of exposure to MgSO4 with brain injury and neurodevelopmental outcomes was examined using multivariable regression analysis adjusting for gestational age at MRI and variables with p value <0.05 on univariate analysis.

Results

Among the 229 neonates, 47 received antenatal MgSO₄. There were no differences between the groups in gestational age and birth weight. MgSO₄ exposure was not associated with an increased risk of necrotizing enterocolitis, chronic lung disease, retinopathy of prematurity, and mortality. The incidence of cerebellar hemorrhage was significantly less in the MgSO₄ group (0% vs. 16%, p value = 0.002). Neonates who received MgSO₄ had lower risks of grade 3–4 intraventricular hemorrhage (IVH) adjusted OR 0.248 (95% CI: 0.092, 0.66), p = 0.006; moderate-severe white matter injury (WMI) adjusted odd ratio 0.208 (95% CI: 0.044, 0.96), p = 0.046; and grade 3–4 IVH and/or moderate-severe WMI adjusted OR 0.23 (95% CI: 0.06, 0.84), p = 0.027. Neurodevelopmental assessment at 36 months corrected age showed better motor (adjusted beta coefficient 1.08 [95% CI: 0.099, 2.06]; p = 0.031) and cognitive composite scores (adjusted beta coefficient 1.29 [95% CI: 0.36, 2.22]; p = 0.007) in the MgSO₄ group.

Conclusion

Antenatal exposure to MgSO₄ in preterm neonates less than 32 weeks was independently associated with lower risks of brain injury and better motor and cognitive outcomes.

Effect of antenatal magnesium sulphate on MRI biomarkers of white matter development at term equivalent age: The MagNUM Study

Background

Magnesium sulphate given to women prior to very preterm birth protects the perinatal brain, so fewer babies die or develop cerebral palsy. How magnesium sulphate exerts these beneficial effects remains uncertain. The MagNUM Study aimed to assess the effect of exposure to antenatal magnesium sulphate on MRI measures of brain white matter microstructure at term equivalent age.

Methods

Nested cohort study within the Magnesium sulphate at 30 to <34 weeks’ Gestational age Neuroprotection Trial (MAGENTA). Australian New Zealand Clinical Trials Registry ACTRN12611000491965. Mothers at risk of preterm birth at 30 to <34 weeks’ gestation were randomised to receive either 4 g of magnesium sulphate heptahydrate [8 mmol magnesium ions], or saline placebo, when preterm birth was planned or expected within 24 h. Participating babies underwent diffusion tensor MRI at term equivalent age. The main outcomes were fractional anisotropy across the white matter tract skeleton compared using Tract-based Spatial Statistics (TBSS), with adjustment for postmenstrual age at birth and at MRI, and MRI site. Researchers and families were blind to treatment group allocation during data collection and analyses.

Findings

Of the 109 babies the demographics of the 49 babies exposed to magnesium sulphate were similar to the 60 babies exposed to placebo. In babies whose mothers were allocated to magnesium sulphate, fractional anisotropy was lower within the corticospinal tracts and corona radiata, the superior and inferior longitudinal fasciculi, and the inferior fronto-occipital fasciculi compared to babies whose mothers were allocated placebo (P < 0·05).

Interpretation

In babies born preterm after 30 weeks’ gestation, antenatal magnesium sulphate exposure did not promote development of white matter microstructure in pathways affecting motor or cognitive function. This suggests that if the neuroprotective effect of magnesium sulphate treatment prior to preterm birth is confirmed at this gestation, the mechanisms are not related to accelerated white matter maturation inferred from fractional anisotropy.

Funding

This study was funded by a project grant from the Health Research Council of New Zealand (HRC 14/153).

Controversies in treatment practices of the mother-infant dyad at the limit of viability

In the setting of threatened extreme preterm birth, balancing maternal and fetal risks and benefits in order to choose the best available treatment options is of utmost importance. Inconsistency in treatment practices for infants born between 22 and 24 weeks of gestatotional age may account for inter-hospital variation in survival rates with and without impairment. Most importantly, non-biased and accurate information must be presented to the family as soon as extremely preterm birth is suspected, including counseling on morbidities and mortality associated with delivery at the limits of viability. This review will focus on different therapeutic medical and surgical practices available for threatened extremely preterm birth to improve fetal and maternal outcomes while highlighting the importance of patient-centered approaches.

Magnesium levels in relation to rates of preterm birth: a systematic review and meta-analysis of ecological, observational, and interventional studies

CONTEXT

Experimental studies suggest that magnesium levels in pregnant women may affect the length of gestation, as magnesium affects the activity of smooth muscle in the uterus. Little is known about the association between magnesium levels or supplementation and the rate of preterm birth.

OBJECTIVE

The aim of this systematic review was to summarize the data on magnesium soil levels and preterm birth rates from ecological, observational, and interventional studies.

DATA SOURCES

Soil magnesium levels were obtained from US Geological Survey data, and preterm birth rates were acquired from the March of Dimes Foundation. Relevant epidemiological and clinical studies published until April 2019 in peer-reviewed journals were retrieved from PubMed, Google Scholar, and related reference lists.

STUDY SELECTION

Original studies published in English, conducted in humans, and in which magnesium (dietary/supplemental intake or biomarkers) was an exposure and preterm birth was an outcome were included.

DATA EXTRACTION

Eleven studies were included in the systematic review. Meta-analysis was performed on 6 studies. Overall relative risk (RR) and corresponding 95%CIs for risk of preterm birth in relation to magnesium supplementation were estimated by a random-effects model.

RESULTS

The ecological study revealed an inverse correlation between magnesium content in soil and rates of preterm birth across the United States (r = -0.68; P < 0.001). Findings from 11 observational studies generally support an inverse association between serum magnesium levels and rates of preterm birth. Of the 6 eligible randomized controlled trials, which included 3068 pregnant women aged 20 to 35 years and 352 preterm infants, the pooled RR was 0.58 (95%CI, 0.35-0.96) for women in the magnesium supplementation group compared with women in the control group.

CONCLUSIONS

Accumulated evidence from ecological, observational, and interventional studies consistently indicates that adequate magnesium intake during pregnancy may help reduce the incidence of preterm birth.

Antenatal magnesium sulfate and intestinal morbidities in preterm infants with extremely low gestational age

BACKGROUND

Antenatal magnesium sulfate is widely used as a tocolytic, for maternal seizures, and for seizure prophylaxis in preeclampsia. Recent studies have suggested that antenatal magnesium sulfate use is associated with favorable neurodevelopmental outcomes in preterm infants. However, there are concerns regarding the effects of antenatal magnesium sulfate on neonates, especially regarding gastrointestinal morbidities. This study aims to explore the effects of antenatal magnesium sulfate on intestinal morbidities requiring surgery in preterm infants.

METHODS

This was a retrospective cohort study of 181 preterm infants who were born at less than 28 weeks of gestational age. Subjects were categorized as infants exposed to antenatal magnesium sulfate and those not exposed to antenatal magnesium sulfate.

RESULTS

Antenatal magnesium sulfate was associated with a decreased risk of surgical conditions of the intestine (OR 0.393, 95% CI 0.170-0.905). The multivariate analysis showed that the duration of antenatal magnesium sulfate use was associated with surgical conditions of the intestine (adjusted OR 0.766, 95% CI 0.589-0.997). In the <26 weeks of gestational age subgroup, the use of antenatal magnesium sulfate was significantly associated with decreased intestinal morbidities requiring surgery (adjusted OR 0.234, 95% CI 0.060-0.922).

CONCLUSION

Antenatal magnesium sulfate use appears to have a protective effect on intestinal morbidities requiring surgery in preterm infants in a duration-dependent manner. Association of antenatal magnesium sulfate use and decreased intestinal morbidities requiring surgery was more distinct in preterm infants <26 weeks of gestational age.

Advances in Management for Preterm Fetuses at Risk of Delivery

Preterm birth accounts for only 11% of live births but contributes to up to 75% of neonatal mortality and more than half of long-term morbidity. Targeted interventions to reduce the most common causes of perinatal morbidity and mortality include intrapartum group B Streptococcus prophylaxis, magnesium sulfate for fetal neuroprotection, antenatal corticosteroids for fetal lung maturity, latency antibiotics for preterm premature rupture of membranes, and tocolysis to allow corticosteroid administration and transfer to a tertiary care center. This article reviews the evidence for interventions to improve outcomes for fetuses at risk for preterm delivery at different gestational ages.

Management of clinical chorioamnionitis: an evidence-based approach

This review aimed to examine the existing evidence about interventions proposed for the treatment of clinical chorioamnionitis, with the goal of developing an evidence-based contemporary approach for the management of this condition. Most trials that assessed the use of antibiotics in clinical chorioamnionitis included patients with a gestational age of ≥34 weeks and in labor. The first-line antimicrobial regimen for the treatment of clinical chorioamnionitis is ampicillin combined with gentamicin, which should be initiated during the intrapartum period. In the event of a cesarean delivery, patients should receive clindamycin at the time of umbilical cord clamping. The administration of additional antibiotic therapy does not appear to be necessary after vaginal or cesarean delivery. However, if postdelivery antibiotics are prescribed, there is support for the administration of an additional dose. Patients can receive antipyretic agents, mainly acetaminophen, even though there is no clear evidence of their benefits. Current evidence suggests that the administration of antenatal corticosteroids for fetal lung maturation and of magnesium sulfate for fetal neuroprotection to patients with clinical chorioamnionitis between 24 0/7 and 33 6/7 weeks of gestation, and possibly between 23 0/7 and 23 6/7 weeks of gestation, has an overall beneficial effect on the infant. However, delivery should not be delayed to complete the full course of corticosteroids and magnesium sulfate. Once the diagnosis of clinical chorioamnionitis has been established, delivery should be considered, regardless of the gestational age. Vaginal delivery is the safer option and cesarean delivery should be reserved for standard obstetrical indications. The time interval between the diagnosis of clinical chorioamnionitis and delivery is not related to most adverse maternal and neonatal outcomes. Patients may require a higher dose of oxytocin to achieve adequate uterine activity or greater uterine activity to effect a given change in cervical dilation. The benefit of using continuous electronic fetal heart rate monitoring in these patients is unclear. We identified the following promising interventions for the management of clinical chorioamnionitis: (1) an antibiotic regimen including ceftriaxone, clarithromycin, and metronidazole that provides coverage against the most commonly identified microorganisms in patients with clinical chorioamnionitis; (2) vaginal cleansing with antiseptic solutions before cesarean delivery with the aim of decreasing the risk of endometritis and, possibly, postoperative wound infection; and (3) antenatal administration of N-acetylcysteine, an antioxidant and antiinflammatory agent, to reduce neonatal morbidity and mortality. Well-powered randomized controlled trials are needed to assess these interventions in patients with clinical chorioamnionitis.

Periviable Premature Rupture of Membranes

Periviable deliveries (less than 26 weeks) are a small percentage of deliveries but account for a disproportionately high number of long-term morbidities. Few studies describe interventions and outcomes for periviable preterm premature rupture of membranes (PPROM). The available reports may include only those neonates who received resuscitation, making interpretation and application difficult. Counseling should consider the impact of oligohydramnios on fetal lung development. This article discusses standard and experimental interventions that may offer neonatal benefit. Antenatal corticosteroids, antibiotics, and magnesium sulfate may improve outcomes but data to support an improvement in outcome are limited. Studies specifically evaluating these interventions are needed.

No. 376-Magnesium Sulphate for Fetal Neuroprotection

OBJECTIVE

The objective is to provide guidelines for the use of antenatal magnesium sulphate for fetal neuroprotection of the preterm infant.

OPTIONS

Antenatal magnesium sulphate administration should be considered for fetal neuroprotection when women present at ≤33 + 6 weeks with imminent preterm birth, defined as a high likelihood of birth because of active labour with cervical dilatation ≥4 cm, with or without preterm pre-labour rupture of membranes, and/or planned preterm birth for fetal or maternal indications. There are no other known fetal neuroprotective agents.

OUTCOMES

The outcomes measured are the incidence of cerebral palsy (CP) and neonatal death.

EVIDENCE

Published literature was retrieved through searches of PubMed or Medline, CINAHL, and the Cochrane Library in December 2017, using appropriate controlled vocabulary and key words (magnesium sulphate, cerebral palsy, preterm birth). Results were restricted to systematic reviews, randomized controlled trials, and relevant observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to December 2017. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1).

BENEFITS, HARMS, AND COSTS

Antenatal magnesium sulphate for fetal neuroprotection reduces the risk of "death or CP" (relative risk [RR] 0.85; 95% confidence interval [CI] 0.74-0.98; 4 trials, 4446 infants), "death or moderate-severe CP" (RR 0.85; 95% CI 0.73-0.99; 3 trials, 4250 infants), "any CP" (RR 0.71; 95% CI 0.55-0.91; 4, trials, 4446 infants), "moderate-to-severe CP" (RR 0.60; 95% CI 0.43-0.84; 3 trials, 4250 infants), and "substantial gross motor dysfunction" (inability to walk without assistance) (RR 0.60; 95% CI 0.43-0.83; 3 trials, 4287 women) at 2 years of age. Results were consistent between trials and across the meta-analyses. There is no anticipated significant increase in health care-related costs because women eligible to receive antenatal magnesium sulphate will be judged to have imminent preterm birth.

VALIDATION

Australian National Clinical Practice Guidelines were published in March 2010 by the Antenatal Magnesium Sulphate for Neuroprotection Guideline Development Panel. Antenatal magnesium sulphate was recommended for fetal neuroprotection in the same dosage as recommended in these guidelines. However, magnesium sulphate was recommended only at <30 weeks gestation, based on 2 considerations. First, no single gestational age subgroup was considered to show a clear benefit. Second, in the face of uncertainty, the committee felt it was prudent to limit the impact of their clinical practice guidelines on resource allocation. In March 2010, the American College of Obstetricians and Gynecologists issued a Committee Opinion on magnesium sulphate for fetal neuroprotection. It stated that "the available evidence suggests that magnesium sulfate given before anticipated early preterm birth reduces the risk of cerebral palsy in surviving infants." No official opinion was given on a gestational age cut-off, but it was recommended that physicians develop specific guidelines around the issues of inclusion criteria, dosage, concurrent tocolysis, and monitoring in accordance with 1 of the larger trials. Similarly, the World Health Organization also strongly recommends use of magnesium sulphate for fetal neuroprotection in its 2015 recommendations on interventions to improve preterm birth outcomes but cites further researching on dosing regimen and re-treatment.

SPONSORS

Canadian Institutes of Health Research (CIHR).

SUMMARY STATEMENT

RECOMMENDATIONS.

Magnesium sulphate for fetal neuroprotection at imminent risk for preterm delivery: a systematic review with meta-analysis and trial sequential analysis

BACKGROUND

Ordinary meta-analyses indicate that magnesium sulphate (MgSO₄ ) treatment in women at imminent risk for preterm delivery decreases the offspring's risk of cerebral palsy (CP). However, repetitive testing of cumulative data calls for statistical caution, e.g. by trial sequential analysis (TSA), for which there are previously insufficient samples to draw a firm conclusion. Recently, a randomised controlled trial (RCT) provided additional data that potentially increased the sample size such that a new TSA might detect a statistically significant effect.

OBJECTIVES

To assess the possible fetal neuroprotective effect of MgSO₄ for women at imminent risk for preterm delivery in an updated systematic review with meta-analysis and TSA.

SEARCH STRATEGY

We searched MEDLINE, Embase, Cochrane and ClinicalTrials.gov on 8 October 2019. The search strategy clustered terms describing the MgSO₄ intervention and preterm delivery.

SELECTION CRITERIA

RCTs.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted the data. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using fixed-effects models. A TSA was applied to the primary outcome, CP. The quality of the evidence was assessed using GRADE. The protocol was registered in PROSPERO (registration: CRD42019151441).

MAIN RESULTS

We identified six eligible trials (5917 women). MgSO₄ intervention in women at imminent risk for preterm birth decreased the offspring's CP risk (meta-analysis RR 0.68, 95% CI 0.54-0.85; TSA RR 0.69, 95% CI 0.48-0.97).

CONCLUSIONS

This systematic review with meta-analysis and TSA shows conclusively that MgSO₄ , when given to women at imminent risk for preterm delivery, decreases the offspring's CP risk.

TWEETABLE ABSTRACT

Antenatal magnesium sulphate decreases the risk of cerebral palsy in children born preterm.

The orphan nuclear receptor Nr4a1 mediates perinatal neuroinflammation in a murine model of preterm labor

Prematurity is associated with perinatal neuroinflammation and injury. Screening for genetic modulators in an LPS murine model of preterm birth revealed the upregulation of Nr4a1, an orphan nuclear transcription factor that is normally absent or limited in embryonic brains. Concurrently, Nr4a1 was downregulated with magnesium sulfate (MgSO₄) and betamethasone (BMTZ) treatments administered to LPS exposed dams. To understand the role of Nr4a1 in perinatal brain injury, we compared the preterm neuroinflammatory response in Nr4a1 knockout (KO) versus wild type (wt) mice. Key inflammatory factors Il1b, Il6 and Tnf, and Iba1+ microglia were significantly lower in Nr4a1 KO versus wt brains exposed to LPS in utero. Treatment with MgSO₄/BMTZ mitigated the neuroinflammatory process in wt but not Nr4a1 KO brains. These results correspond with a reduction in cerebral hemorrhage in wt but not mutant embryos from dams given MgSO₄/BMTZ. Further analysis with Nr4a1-GFP-Cre × tdTomato loxP reporter mice revealed that the upregulation of Nr4a1 with perinatal neuroinflammation occurs in the cerebral vasculature. Altogether, this study implicates Nr4a1 in the developing vasculature as a potent mediator of neuroinflammatory brain injury that occurs with preterm birth. It is also possible that MgSO₄/BMTZ mitigates this process by direct or indirect inhibition of Nr4a1.

Antenatal magnesium sulphate and adverse neonatal outcomes: A systematic review and meta-analysis

BACKGROUND

There is widespread, increasing use of magnesium sulphate in obstetric practice for pre-eclampsia, eclampsia, and preterm fetal neuroprotection; benefit for preventing preterm labour and birth (tocolysis) is unproven. We conducted a systematic review and meta-analysis to assess whether antenatal magnesium sulphate is associated with unintended adverse neonatal outcomes.

METHODS AND FINDINGS

CINAHL, Cochrane Library, LILACS, MEDLINE, Embase, TOXLINE, and Web of Science, were searched (inceptions to 3 September 2019). Randomised, quasi-randomised, and non-randomised trials, cohort and case-control studies, and case reports assessing antenatal magnesium sulphate for pre-eclampsia, eclampsia, fetal neuroprotection, or tocolysis, compared with placebo/no treatment or a different magnesium sulphate regimen, were included. The primary outcome was perinatal death. Secondary outcomes included pre-specified and non-pre-specified adverse neonatal outcomes. Two reviewers screened 5,890 articles, extracted data, and assessed risk of bias following Cochrane Handbook and RTI Item Bank guidance. For randomised trials, pooled risk ratios (RRs) or mean differences, with 95% confidence intervals (CIs), were calculated using fixed- or random-effects meta-analysis. Non-randomised data were tabulated and narratively summarised. We included 197 studies (40 randomised trials, 138 non-randomised studies, and 19 case reports), of mixed quality. The 40 trials (randomising 19,265 women and their babies) were conducted from 1987 to 2018 across high- (16 trials) and low/middle-income countries (23 trials) (1 mixed). Indications included pre-eclampsia/eclampsia (24 trials), fetal neuroprotection (7 trials), and tocolysis (9 trials); 18 trials compared magnesium sulphate with placebo/no treatment, and 22 compared different regimens. For perinatal death, no clear difference in randomised trials was observed between magnesium sulphate and placebo/no treatment (RR 1.01; 95% CI 0.92 to 1.10; 8 trials, 13,654 babies), nor between regimens. Eleven of 138 non-randomised studies reported on perinatal death. Only 1 cohort (127 babies; moderate to high risk of bias) observed an increased risk of perinatal death with >48 versus ≤48 grams magnesium sulphate exposure for tocolysis. No clear secondary adverse neonatal outcomes were observed in randomised trials, and a very limited number of possible adverse outcomes warranting further consideration were identified in non-randomised studies. Where non-randomised studies observed possible harms, often no or few confounders were controlled for (moderate to high risk of bias), samples were small (200 babies or fewer), and/or results were from subgroup analyses. Limitations include missing data for important outcomes across most studies, heterogeneity of included studies, and inclusion of published data only.

CONCLUSIONS

Our findings do not support clear associations between antenatal magnesium sulphate for beneficial indications and adverse neonatal outcomes. Further large, high-quality studies (prospective cohorts or individual participant data meta-analyses) assessing specific outcomes, or the impact of regimen, pregnancy, or birth characteristics on these outcomes, would further inform safety recommendations. PROSPERO: CRD42013004451.

Recent advances in perinatal neuroprotection

Perinatal brain injury is a major cause of neurological disability in both premature and term infants. In this review, we summarize the evidence behind some established neuroprotective practices such as administration of antenatal steroids, intrapartum magnesium for preterm delivery, and therapeutic hypothermia. In addition, we examine emerging practices such as delayed cord clamping, postnatal magnesium administration, recombinant erythropoietin, and non-steroidal anti-inflammatory agents and finally inform the reader about novel interventions, some of which are currently in trials, such as xenon, melatonin, topiramate, allopurinol, creatine, and autologous cord cell therapy.

Magnesium Sulfate and Novel Therapies to Promote Neuroprotection

Cerebral palsy occurs more often in preterm than in term deliveries and is one of the major neurologic injuries seen in preterm infants. Magnesium sulfate has been found to reduce the risk of cerebral palsy in patients at risk of delivery before 32 weeks' gestational age. Multiple large clinical trials have shown this effect. The authors recommend magnesium sulfate bolus followed by continuous dosing of magnesium sulfate in those at risk of delivery before 32 weeks' gestation until delivery occurs or is no longer imminent. This article also discusses novel and emerging therapies for the prevention of cerebral palsy.

The role of magnesium sulfate (MgSO4) in fetal neuroprotection

Prevention of neurologic disability associated with preterm birth is one of the major challenges in current perinatal medicine. Magnesium sulfate (MgSO₄), the focus of this review has been proposed as major step forward for that matter. MgSO₄ is easily accessible, cheap, and has been proposed as a mandatory part of the management of inevitable preterm birth. The results of the various RCT's on the use of MgSO₄ for neuroprotection has been the subject of many systematic reviews, other studies focused on dosing schedules, side effects and only a few focused on exploring magnesium's mechanism of action. Meanwhile, many guidelines worldwide have plugged MgSO₄ as an essential ingredient of daily best practice when managing inevitable preterm birth because it has been shown to reduce the risk of severe neurologic deficit, in particular, cerebral palsy in appropriately selected patients. The more premature, the greater benefit associated with the use of antenatal MgSO₄. The dose of 4 g given intravenously 15 min continued by 1 g/h until maximum 24 h and minimum for 4 h is the standard regiment proposed in most guidelines. It should be noted, however, that a recent study found that a total dose of 64 g was associated with the maximum protective effect. Only the protocol used by the largest RCT, the BEAM trial, with a loading dose of 6 g initially followed by a 2-g/h maintenance dose, if continued for 24 h would give a total dose over 50 g. Other studies report on an increased risk of neonatal death with these high doses. Several studies expressed concerns about the risk of serious side effects for both mother and neonate. The results from the systematic review showed that the most commonly used dosage, 4 g bolus continued by 1 g/h maintenance, did not increase neonatal mortality and other suspected neonatal complication such as neonatal asphyxia, spontaneous intestinal perforation, necrotizing enterocolitis, and feeding intolerance. Giving a single bolus injection of 4 g MgSO4 for stimulating BDNF production in highly "suspicious" preterm labor, and 4 g again when preterm birth become inevitable may be best from a safety perspective and also appears to have a stronger rationale.

Survey on use of antenatal magnesium sulphate for fetal neuroprotection prior to preterm birth in Australia and New Zealand - Ongoing barriers and enablers

BACKGROUND

Clinical practice guidelines recommend the use of antenatal magnesium sulphate for fetal neuroprotection before preterm birth at <30 weeks' gestation.

AIMS

This survey assessed the use of antenatal magnesium sulphate for fetal neuroprotection to determine if use has changed since the previous survey in 2012, and to evaluate enablers and barriers to use.

MATERIALS AND METHODS

A questionnaire was sent to clinical leaders at 29 hospitals with a neonatal intensive care unit in Australia and New Zealand asking at what gestational ages magnesium sulphate was given, if use was audited and any enablers and barriers  to use.

RESULTS

Responses were received for 24 (83%) hospitals. The use of magnesium sulphate for fetal neuroprotection was reported as 89% (IQR 80-90%), an increase from 80% (IQR 53-90%) from the earlier survey. The majority of health professionals were reported as using magnesium sulphate at <30 weeks' gestation. The top enablers for use of magnesium sulphate were availability of pamphlets, posters, case record stickers and PowerPoint presentations. The main reasons as to why eligible women did not receive magnesium sulphate were imminent birth, the hospital being short staffed and the patient declined. The use of antenatal magnesium sulphate has been or is being audited in 11 (46%) of the hospitals.

CONCLUSIONS

Clinical leaders at institutions in Australia and New Zealand report that uptake in the use of magnesium sulphate for fetal neuroprotection has continued to increase since the earlier, bi-national survey in 2012. Barriers to the use of magnesium sulphate identified have institutional and consumer implications.

Intrapartum magnesium sulfate is associated with neuroprotection in growth-restricted fetuses

BACKGROUND

Intrapartum magnesium sulfate administration is recommended for fetal neuroprotection in women with imminent very preterm birth. However, previous studies have not included or separately analyzed the outcomes of pregnancies with fetal growth restriction that were treated with intrapartum magnesium sulfate.

OBJECTIVE

We sought to evaluate the neonatal and neurodevelopmental outcomes of growth-restricted fetuses born <29 weeks' gestation and exposed to maternal intrapartum magnesium sulfate.

STUDY DESIGN

We conducted a retrospective cohort study of infants born <29 weeks' gestation from 2010 through 2011, admitted to participating Canadian Neonatal Network units, and followed by the Canadian Neonatal Follow-up Network centers. Growth restriction was defined either as estimated fetal or actual neonatal birthweight <10th percentile according to fetal or neonatal growth standards for gestational age and sex, respectively. Infants exposed to intrapartum magnesium sulfate were compared with unexposed infants. The primary outcome was composite of death or significant neurodevelopmental impairment at 18-36 months' corrected age. Secondary outcomes were death or any neurodevelopmental impairment at 18-36 months' corrected age. Neonatal morbidities were also compared.

RESULTS

Of the 336 growth-restricted fetuses, 112 (33%) received magnesium sulfate and of the 177 growth-restricted infants, 61 (34%) received magnesium sulfate. Administration of magnesium sulfate was at the discretion of the treating physician. Intrapartum magnesium sulfate was associated with reduced odds of composite of death or significant neurodevelopmental impairment for infants classified according to both fetal standards (adjusted odds ratio, 0.42; 95% confidence interval, 0.22-0.80) and neonatal standards (adjusted odds ratio, 0.44; 95% confidence interval, 0.20-0.98).

CONCLUSION

Intrapartum administration of magnesium sulfate to women with growth-restricted fetuses born <29 weeks' gestation was associated with reduced odds of composite of death or significant neurodevelopmental impairment.

Association of histological chorioamnionitis and magnesium sulfate treatment in singleton and dichorionic twin pregnancies with preterm premature rupture of membranes: preliminary observations

Objective To evaluate the possible association between antenatal magnesium sulfate treatment with histological chorioamnionitis in patients with singleton or dichorionic twins that had preterm premature rupture of the membranes. Methods This was an observational study performed in patients admitted to the hospital with rupture of membranes before 34 weeks' gestation. The primary outcome was histological chorioamnionitis and the primary predictor was antenatal magnesium sulfate treatment. A logistic regression model was used without consideration of other antenatal medical treatments. Results Among 107 patients with preterm deliveries, 57 were admitted to the hospital before 34 weeks' gestation with preterm premature rupture of membranes. Fifty-cases were excluded from the analysis because they were admitted after 34 weeks' gestation, delivered before 24 weeks' gestation or had intrauterine fetal demise or monochorionic twins. The logistic regression analysis adjusting for maternal age, gravidity, parity, multiple gestation, gestational age at delivery, and birthweight, indicated that patients with singleton pregnancies and histological chorioamnionitis had received magnesium sulfate antenatally more frequently (χ2=6.46; P=0.01). The association between histological chorioamnionitis and magnesium sulfate treatment was not found among patients with dichorionic twin pregnancies with one intact gestational sac. Conclusions In this cohort of patients with preterm premature rupture of membranes admitted to the hospital before 34 week's gestation, those with singleton pregnancies treated antenatally with magnesium sulfate for neonatal neuroprotection had a greater rate of histological chorioamnionitis.

Economic evaluation and cost of interventions for cerebral palsy: a systematic review

AIM

Economic appraisal can help guide policy-making for purchasing decisions, and treatment and management algorithms for health interventions. We conducted a systematic review of economic studies in cerebral palsy (CP) to inform future research.

METHOD

Economic studies published since 1970 were identified from seven databases. Two reviewers independently screened abstracts and extracted data following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Any discrepancies were resolved by discussion.

RESULTS

Of 980 identified references, 115 were included for full-text assessment. Thirteen articles met standard criteria for a full economic evaluation, two as partial economic evaluations, and 18 as cost studies. Six were full economic evaluations alongside clinical studies or randomized controlled trials, whereas seven involved modelling simulations. The economic case for administration of magnesium sulfate for imminent preterm birth is compelling, achieving both health gain and cost savings. Current literature suggests intrathecal baclofen therapy and botulinum toxin injection are cost-effective, but stronger evidence for long-term effects is needed. Lifestyle and web-based interventions are inexpensive, but broader measurement of outcomes is required.

INTERPRETATION

Prevention of CP would avoid significant economic burden. Some treatments and interventions have been shown to be cost-effective, although stronger evidence of clinical effectiveness is needed. What this paper adds Cost-effectiveness evidence shows prevention is the most significant strategy. Some treatments are cost-effective, but stronger evidence for long-term effectiveness is required. Comparison of treatment costs is challenging owing to variations in methodologies and varying clinical indications.

Safety Assessment of Magnesium Sulfate as Used in Cosmetics

The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the safety of magnesium sulfate, which functions as a bulking agent in cosmetic products and is reportedly used at concentrations up to 11% and 25% in leave-on and rinse-off products, respectively. The Panel noted that the history of safe medical use of magnesium sulfate provides further confidence that there are no significant toxicity concerns relating to systemic exposure to this ingredient after cosmetic product application. Furthermore, the extensive clinical experience of the Panel, including the results of numerous patch tests, indicates that magnesium salts do not have the potential to induce sensitization. The Panel also noted that results were negative for 50% magnesium sulfate in a mouse skin irritation study and in an in vitro sensitization assay. The Panel concluded that magnesium sulfate is safe in cosmetics in the present practices of use and concentration described in the safety assessment.

Fetal Neuroprotection by Magnesium Sulfate: From Translational Research to Clinical Application

Despite improvements in perinatal care, preterm birth still occurs regularly and the associated brain injury and adverse neurological outcomes remain a persistent challenge. Antenatal magnesium sulfate administration is an intervention with demonstrated neuroprotective effects for preterm births before 32 weeks of gestation (WG). Owing to its biological properties, including its action as an N-methyl-d-aspartate receptor blocker and its anti-inflammatory effects, magnesium is a good candidate for neuroprotection. In hypoxia models, including hypoxia-ischemia, inflammation, and excitotoxicity in various species (mice, rats, pigs), magnesium sulfate preconditioning decreased the induced lesions’ sizes and inflammatory cytokine levels, prevented cell death, and improved long-term behavior. In humans, some observational studies have demonstrated reduced risks of cerebral palsy after antenatal magnesium sulfate therapy. Meta-analyses of five randomized controlled trials using magnesium sulfate as a neuroprotectant showed amelioration of cerebral palsy at 2 years. A meta-analysis of individual participant data from these trials showed an equally strong decrease in cerebral palsy and the combined risk of fetal/infant death and cerebral palsy at 2 years. The benefit remained similar regardless of gestational age, cause of prematurity, and total dose received. These data support the use of a minimal dose (e.g., 4 g loading dose ± 1 g/h maintenance dose over 12 h) to avoid potential deleterious effects. Antenatal magnesium sulfate is now recommended by the World Health Organization and many pediatric and obstetrical societies, and it is requisite to maximize its administration among women at risk of preterm delivery before 32 WG.

Antenatal glucocorticoids, magnesium sulfate, and mode of birth in preterm fetal small for gestational age

A diagnosis of fetal growth restriction and subsequent preterm birth is associated with increased risks of adverse perinatal and neurodevelopmental outcomes and potentially long-lasting effects to adulthood. Most such cases are associated with placental insufficiency and the fetal response to chronic intrauterine hypoxemia and nutrient deprivation leads to substantial physiological and metabolic adaptations. The management of such pregnancies, especially with respect to perinatal interventions and birth mode, remains an unresolved dilemma. The benefits from standard interventions for threatened preterm birth may not be necessarily translated to pregnancies with small-for-gestational-age fetuses. Clinical trials or retrospective studies on outcomes following administration of antenatal glucocorticoids and magnesium sulfate for neuroprotection when preterm birth is imminent either have yielded conflicting results for small-for-gestational-age fetuses, or did not include this subgroup of patients. Experimental models highlight potential harmful effects of administration of antenatal glucocorticoids and magnesium sulfate in the pregnancies with fetal small for gestational age although clinical data do not substantiate these concerns. In addition, heterogeneity in definitions of fetal small for gestational age, variations in the inclusion criteria, and the glucocorticoid regime contribute to inconsistent results. In this review, we discuss the physiologic adaptions of the small-for-gestational-age fetus to its abnormal in utero environment in relation to antenatal glucocorticoids; the impact of antenatal glucocorticoids and intrapartum magnesium sulfate in pregnancies with fetal small for gestational age; the current literature on birth mode for pregnancies with fetal small for gestational age; and the knowledge gaps in the existing literature.

Antenatal magnesium sulfate is beneficial or harmful in very preterm and extremely preterm neonates: a new insight

AIMS

To evaluate whether antenatal MgSO₄ is beneficial or harmful in very preterm and extremely preterm neonates.

MATERIALS AND METHODS

We retrieved published literature through searches of PubMed or Medline, CINAHL, and the Cochrane Library. Results were restricted to systematic reviews, meta-analysis, randomized controlled trials (RCTs), and relevant observational studies.

RESULTS

Evidence revealed that antenatal MgSO₄ has neuroprotective role in preterm neonates and it decreased the risk of cerebral palsy and gross motor dysfunction. Evidences regarding association of antenatal MgSO₄ with feed intolerance, NEC and SIP were from cohort studies and controversial.

CONCLUSIONS

We should continue use antenatal MgSO₄ to all eligible patients according to protocol till the more robust evidence will suggest association with gastrointestinal complications. In the meantime, we should have a high index of suspicion of gastrointestinal complications in extremely preterms particularly <26 weeks of gestation.

MAGnesium sulphate for fetal neuroprotection to prevent Cerebral Palsy (MAG-CP)-implementation of a national guideline in Canada

BACKGROUND

Evidence supports magnesium sulphate (MgSO4) for women at risk of imminent birth at < 32-34 weeks to reduce the likelihood of cerebral palsy in the child. MAGnesium sulphate for fetal neuroprotection to prevent Cerebral Palsy (MAG-CP) was a multifaceted knowledge translation (KT) strategy for this practice.

METHODS

The KT strategy included national clinical practice guidelines, a national online e-learning module and, at MAG-CP sites, educational rounds, focus group discussions and surveys of barriers and facilitators. Participating sites contributed data on pregnancies with threatened very preterm birth. In an interrupted time-series study design, MgSO4 use for fetal neuroprotection (NP) was tracked prior to (Aug 2005-May 2011) and during (Jun 2011-Sept 2015) the KT intervention. Effectiveness of the strategy was measured by optimal MgSO4 use (i.e. administration when and only when indicated) over time, evaluated by a segmented generalised estimating equations logistic regression (p < 0.05 significant). Secondary outcomes included maternal effects and, using the Canadian Neonatal Network (CNN) database, national trends in MgSO4 use for fetal NP and associated neonatal resuscitation. With an anticipated recruitment of 3752 mothers over 4 years at Canadian Perinatal Network sites, we anticipated > 95% power to detect an increase in optimal MgSO4 use for fetal NP from < 5 to 80% (2-sided, alpha 0.05) and at least 80% power to detect any increases observed in maternal side effects from RCTs.

RESULTS

Seven thousand eight hundred eighty-eight women with imminent preterm birth were eligible for MgSO4 for fetal NP: 4745 pre-KT (18 centres) and 3143 during KT (11 centres). The KT intervention was associated with an 84% increase in the odds of optimal use (OR 1.00 to 1.84, p < 0.001), a reduction in the odds of underuse (OR 1.00 to 0.47, p < 0.001) and an increase in suboptimal use (too early or at ≥ 32 weeks; OR 1.18 to 2.18, p < 0.001) of MgSO4 for fetal NP. Maternal hypotension was uncommon (7/1512, 0.5%). Nationally, intensive neonatal resuscitation decreased (p = 0.024) despite rising MgSO4 use for fetal NP (p < 0.001).

CONCLUSION

Multifaceted KT was associated with significant increases in use of MgSO4 for fetal NP, with neither important maternal nor neonatal risks.

Magnesium sulfate and fetal neuroprotection: overview of clinical evidence

Antenatal administration of magnesium sulfate is an important part of the neuroprotective strategy for preterm infants. Strong evidence from five randomized controlled trials and five meta-analyses has demonstrated that magnesium sulfate, when administered before preterm delivery, significantly reduces the risk of cerebral palsy at two years. Through secondary analyses of randomized controlled trials and other original clinical studies, this state-of-the-art review highlights the absence of serious adverse effects in both pregnant women and neonates, as well as the impact of maternal body mass index and preeclamptic status on the maternal and neonatal magnesium levels, which could influence the magnitude of the neuroprotective effect. Although antenatal magnesium sulfate is a cost-effective strategy, some practice surveys have demonstrated that the use of magnesium sulfate is not sufficient and that its use is heterogeneous, differing among different maternity wards. Since 2010, an increasing number of obstetrical societies have recommended its use to improve the neurological outcomes of preterm infants, especially the International Federation of Gynecology and Obstetrics and World Health Organization in 2015, and France in 2017. Considering the neuroprotective impact of magnesium sulfate when administered before delivery, postnatal administration should be considered, and its effects should be assessed using randomized controlled trials.

Association between Intrapartum Magnesium Administration and the Incidence of Maternal Fever: A Retrospective Cross-sectional Study

BACKGROUND

Intrapartum maternal fever is associated with several adverse neonatal outcomes. Intrapartum fever can be infectious or inflammatory in etiology. Increases in interleukin 6 and other inflammatory markers are associated with maternal fever. Magnesium has been shown to attenuate interleukin 6-mediated fever in animal models. We hypothesized that parturients exposed to intrapartum magnesium would have a lower incidence of fever than nonexposed parturients.

METHODS

In this study, electronic medical record data from all deliveries at Northwestern Memorial Hospital (Chicago, Illinois) between 2007 and 2014 were evaluated. The primary outcome was intrapartum fever (temperature at or higher than 38.0°C). Factors associated with the development of maternal fever were evaluated using a multivariable logistic regression model. Propensity score matching was used to reduce potential bias from nonrandom selection of magnesium administration.

RESULTS

Of the 58,541 women who met inclusion criteria, 5,924 (10.1%) developed intrapartum fever. Febrile parturients were more likely to be nulliparous, have used neuraxial analgesia, and have been delivered via cesarean section. The incidence of fever was lower in women exposed to magnesium (6.0%) than those who were not (10.2%). In multivariable logistic regression, women exposed to magnesium were less likely to develop a fever (adjusted odds ratio = 0.42 [95% CI, 0.31 to 0.58]). After propensity matching (N = 959 per group), the odds ratio of developing fever was lower in women who received magnesium therapy (odds ratio = 0.68 [95% CI, 0.48 to 0.98]).

CONCLUSIONS

Magnesium may play a protective role against the development of intrapartum fever. Future work should further explore the association between magnesium dosing and the incidence of maternal fever.

Intrauterine Growth Restriction. Guideline of the German Society of Gynecology and Obstetrics (S2k-Level, AWMF Registry No. 015/080, October 2016)

AIMS

The aim of this official guideline published and coordinated by the German Society of Gynecology and Obstetrics (DGGG) was to provide consensus-based recommendations obtained by evaluating the relevant literature for the diagnostic treatment and management of women with fetal growth restriction.

METHODS

This S2k guideline represents the structured consensus of a representative panel of experts with a range of different professional backgrounds commissioned by the Guideline Committee of the DGGG.

RECOMMENDATIONS

Recommendations for diagnostic treatment, management, counselling, prophylaxis and screening are presented.

Serum Magnesium Levels in Preterm Infants Are Higher Than Adult Levels: A Systematic Literature Review and Meta-Analysis

Magnesium (Mg) is an essential mineral in the body, impacting the synthesis of biomacromolecules, bone matrix development, energy production, as well as heart, nerve, and muscle function. Although the importance of Mg is evident, reference values for serum Mg (sMg) in pediatric patients (more specifically, in neonates) are not well established. This systematic literature review and meta-analysis (using 47 eligible studies) aims to quantify normal and tolerable ranges of sMg concentrations during the neonatal period and to highlight the factors influencing Mg levels and the importance of regulating sMg levels during pregnancy and birth. In newborns without Mg supplementation during pregnancy, magnesium levels at birth (0.76 (95% CI: 0.52, 0.99) mmol/L) were similar to that of mothers during pregnancy (0.74 (95% CI: 0.43, 1.04) mmol/L), but increased during the first week of life (0.91 (95% CI: 0.55, 1.26) mmol/L) before returning to adult levels. This pattern was also seen in newborns with Mg supplementation during pregnancy, where the average was 1.29 (95% CI: 0.50, 2.08) mmol/L at birth and 1.44 (95% CI: 0.61, 2.27) mmol/L during the first week of life. Factors influencing these levels include prenatal Mg supplementation, gestational age, birth weight, renal maturity/function, and postnatal Mg intake. Elevated Mg levels (>2.5 mmol/L) have been associated with an increased risk of mortality, admission into intensive care, hypotonia, hypotension, and respiratory depression but sMg concentrations up to 2.0 mmol/L appear to be well tolerated in neonates, requiring adequate survey and minimal intervention.

Assessing the neuroprotective benefits for babies of antenatal magnesium sulphate: An individual participant data meta-analysis

BACKGROUND

Babies born preterm are at an increased risk of dying in the first weeks of life, and those who survive have a higher rate of cerebral palsy (CP) compared with babies born at term. The aim of this individual participant data (IPD) meta-analysis (MA) was to assess the effects of antenatal magnesium sulphate, compared with no magnesium treatment, given to women at risk of preterm birth on important maternal and fetal outcomes, including survival free of CP, and whether effects differed by participant or treatment characteristics such as the reason the woman was at risk of preterm birth, why treatment was given, the gestational age at which magnesium sulphate treatment was received, or the dose and timing of the administration of magnesium sulphate.

METHODS AND FINDINGS

Trials in which women considered at risk of preterm birth (<37 weeks' gestation) were randomised to magnesium sulphate or control treatment and where neurologic outcomes for the baby were reported were eligible for inclusion. The primary outcomes were infant death or CP and severe maternal outcome potentially related to treatment. Studies were identified based on the Cochrane Pregnancy and Childbirth search strategy using the terms [antenatal or prenatal] and [magnesium] and [preterm or premature or neuroprotection or 'cerebral palsy']. The date of the last search was 28 February 2017. IPD were sought from investigators with eligible trials. Risk of bias was assessed using criteria from the Cochrane Collaboration. For each prespecified outcome, IPD were analysed using a 1-stage approach. All 5 trials identified were included, with 5,493 women and 6,131 babies. Overall, there was no clear effect of magnesium sulphate treatment compared with no treatment on the primary infant composite outcome of death or CP (relative risk [RR] 0.94, 95% confidence interval (CI) 0.85 to 1.05, 6,131 babies, 5 trials, p = 0.07 for heterogeneity of treatment effect across trials). In the prespecified sensitivity analysis restricted to data from the 4 trials in which the intent of treatment was fetal neuroprotection, there was a significant reduction in the risk of death or CP with magnesium sulphate treatment compared with no treatment (RR 0.86, 95% CI 0.75 to 0.99, 4,448 babies, 4 trials), with no significant heterogeneity (p = 0.28). The number needed to treat (NNT) to benefit was 41 women/babies to prevent 1 baby from either dying or having CP. For the primary outcome of severe maternal outcome potentially related to magnesium sulphate treatment, no events were recorded from the 2 trials providing data. When the individual components of the composite infant outcome were assessed, no effect was seen for death overall (RR 1.03, 95% CI 0.91 to 1.17, 6,131 babies, 5 trials) or in the analysis of death using only data from trials with the intent of fetal neuroprotection (RR 0.95, 95% CI 0.80 to 1.13, 4,448 babies, 4 trials). For cerebral palsy in survivors, magnesium sulphate treatment had a strong protective effect in both the overall analysis (RR 0.68, 95% CI 0.54 to 0.87, 4,601 babies, 5 trials, NNT to benefit 46) and the neuroprotective intent analysis (RR 0.68, 95% CI 0.53 to 0.87, 3,988 babies, 4 trials, NNT to benefit 42). No statistically significant differences were seen for any of the other secondary outcomes. The treatment effect varied little by the reason the woman was at risk of preterm birth, the gestational age at which magnesium sulphate treatment was given, the total dose received, or whether maintenance therapy was used. A limitation of the study was that not all trials could provide the data required for the planned analyses so that combined with low event rates for some important clinical events, the power to find a difference was limited.

CONCLUSIONS

Antenatal magnesium sulphate given prior to preterm birth for fetal neuroprotection prevents CP and reduces the combined risk of fetal/infant death or CP. Benefit is seen regardless of the reason for preterm birth, with similar effects across a range of preterm gestational ages and different treatment regimens. Widespread adoption worldwide of this relatively inexpensive, easy-to-administer treatment would lead to important global health benefits for infants born preterm.

Antenatal magnesium sulphate administration for fetal neuroprotection: a French national survey

Background

Magnesium sulphate (MgSO₄) is the only treatment approved for fetal neuroprotection. No information on its use is available in the absence of a national registry of neonatal practices. The objective of our study was to evaluate the use of MgSO₄ for fetal neuroprotection in French tertiary maternity hospitals (FTMH).

Methods

Online and phone survey of all FTMH between August 2014 and May 2015. A participation was expected from one senior obstetrician, one senior anaesthetist and one senior neonatologist from each FTMH. Information was obtained from 63/63 (100%) FTMH and 138/189 (73%) physicians. Use of MgSO₄ for fetal neuroprotection, regimen and injection protocols, reasons for non-use were the main outcome measures.

Results

60.3% of FTMH used MgSO₄ for fetal neuroprotection. No significant difference was observed between university and non-university hospitals or according to the annual number of births. Protocols differed especially in terms of the maximum gestational age (3% <28 WG, 71% <33 WG, 18% <34 WG and 8% < 35 WG). Eighty seven percent of centers using MgSO₄ prescribed retreatment when necessary, but according to non-consensual modalities in terms of number of treatments or between-treatment intervals. Injections and monitoring were mostly performed in the delivery room (97%) but also in the recovery room in one half of hospitals. Lack of experience (52%), absence of a written protocol (49%) and national guidelines (46%) were the reasons most commonly reported to explain non-use of MgSO₄ as a neuroprotective agent.

Conclusions

Sixty percent of FTMH used MgSO₄ for fetal neuroprotection, but according to heterogeneous regimens. National guidelines could allow standardization of practices and better MgSO₄ coverage.

Medical and Surgical Interventions Available Before a Periviable Birth

Periviable birth contributes disproportionately to perinatal morbidity and mortality. By analyzing the most relevant outcomes after a preterm birth some information can be provided on the potential benefit of interventions. This article discusses surgical and medical interventions that may offer neonatal benefit including cerclage, amniocentesis, progesterone, antenatal corticosteroids, magnesium sulfate for neuroprotection, and tocolysis. Cervical cerclage has the greatest promise at reducing morbidity and mortality related to periviable birth even though it may not reduce the overall preterm birth rate. The use of antenatal corticosteroids, magnesium sulfate, progesterone, and tocolytics may also improve outcome. Studies specifically evaluating these interventions are needed.

Antenatal Exposure to Magnesium Sulfate Is Associated with Reduced Cerebellar Hemorrhage in Preterm Newborns

OBJECTIVE

To determine the association of antenatal magnesium sulfate with cerebellar hemorrhage in a prospective cohort of premature newborns evaluated by magnetic resonance imaging (MRI).

STUDY DESIGN

Cross-sectional analysis of baseline characteristics from a prospective cohort of preterm newborns (<33 weeks gestation) evaluated with 3T-MRI shortly after birth. Exclusion criteria were clinical evidence of a congenital syndrome, congenital infection, or clinical status too unstable for transport to MRI. Antenatal magnesium sulfate exposure was abstracted from the medical records and the indication was classified as obstetric or neuroprotection. Two pediatric neuroradiologists, blinded to the clinical history, scored axial T2-weighted and iron susceptibility MRI sequences for cerebellar hemorrhage. The association of antenatal magnesium sulfate with cerebellar hemorrhage was evaluated using multivariable logistic regression, adjusting for postmenstrual age at MRI and known predictors of cerebellar hemorrhage.

RESULTS

Cerebellar hemorrhage was present in 27 of 73 newborns (37%) imaged at a mean ± SD postmenstrual age of 32.4 ± 2 weeks. Antenatal magnesium sulfate exposure was associated with a significantly reduced risk of cerebellar hemorrhage. Adjusting for postmenstrual age at MRI, and predictors of cerebellar hemorrhage, antenatal magnesium sulfate was independently associated in our cohort with decreased cerebellar hemorrhage (OR, 0.18; 95% CI, 0.049-0.65; P = .009).

CONCLUSION

Antenatal magnesium sulfate exposure is independently associated with a decreased risk of MRI-detected cerebellar hemorrhage in premature newborns, which could explain some of the reported neuroprotective effects of magnesium sulfate.