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

Factors influencing appropriate use of interventions for management of women experiencing preterm birth: A mixed-methods systematic review and narrative synthesis

BACKGROUND

Preterm birth-related complications are the leading cause of death in newborns and children under 5. Health outcomes of preterm newborns can be improved with appropriate use of antenatal corticosteroids (ACSs) to promote fetal lung maturity, tocolytics to delay birth, magnesium sulphate for fetal neuroprotection, and antibiotics for preterm prelabour rupture of membranes. However, there are wide disparities in the rate and consistency in the use of these interventions across settings, which may underlie the differential health outcomes among preterm newborns. We aimed to assess factors (barriers and facilitators) affecting the appropriate use of ACS, tocolytics, magnesium sulphate, and antibiotics to improve preterm birth management.

METHODS AND FINDINGS

We conducted a mixed-methods systematic review including primary qualitative, quantitative, and mixed-methods studies. We searched MEDLINE, EMBASE, CINAHL, Global Health, and grey literature from inception to 16 May 2022. Eligible studies explored perspectives of women, partners, or community members who experienced preterm birth or were at risk of preterm birth and/or received any of the 4 interventions, health workers providing maternity and newborn care, and other stakeholders involved in maternal care (e.g., facility managers, policymakers). We used an iterative narrative synthesis approach to analysis, assessed methodological limitations using the Mixed Methods Appraisal Tool, and assessed confidence in each qualitative review finding using the GRADE-CERQual approach. Behaviour change models (Theoretical Domains Framework; Capability, Opportunity, and Motivation (COM-B)) were used to map barriers and facilitators affecting appropriate use of these interventions. We included 46 studies from 32 countries, describing factors affecting use of ACS (32/46 studies), tocolytics (13/46 studies), magnesium sulphate (9/46 studies), and antibiotics (5/46 studies). We identified a range of barriers influencing appropriate use of the 4 interventions globally, which include the following: inaccurate gestational age assessment, inconsistent guidelines, varied knowledge, perceived risks and benefits, perceived uncertainties and constraints in administration, confusion around prescribing and administering authority, and inadequate stock, human resources, and labour and newborn care. Women reported hesitancy in accepting interventions, as they typically learned about them during emergencies. Most included studies were from high-income countries (37/46 studies), which may affect the transferability of these findings to low- or middle-income settings.

CONCLUSIONS

In this study, we identified critical factors affecting implementation of 4 interventions to improve preterm birth management globally. Policymakers and implementers can consider these barriers and facilitators when formulating policies and planning implementation or scale-up of these interventions. Study findings can inform clinical preterm birth guidelines and implementation to ensure that barriers are addressed, and enablers are reinforced to ensure these interventions are widely available and appropriately used globally.

Effect of Neuroprotective Magnesium Sulfate Treatment on Brain Transcription Response to Hypoxia Ischemia in Neonate Mice

MgSO₄ is widely used in the prevention of preterm neurological disabilities but its modes of action remain poorly established. We used a co-hybridization approach using the transcriptome in 5-day old mice treated with a single dose of MgSO₄ (600 mg/kg), and/or exposed to hypoxia-ischemia (HI). The transcription of hundreds of genes was altered in all the groups. MgSO₄ mainly produced repressions culminating 6 h after injection. Bio-statistical analysis revealed the repression of synaptogenesis and axonal development. The putative targets of MgSO₄ were Mnk1 and Frm1. A behavioral study of adults did not detect lasting effects of neonatal MgSO₄ and precluded NMDA-receptor-mediated side effects. The effects of MgSO₄ plus HI exceeded the sum of the effects of separate treatments. MgSO₄ prior to HI reduced inflammation and the innate immune response probably as a result of cytokine inhibition (Ccl2, Ifng, interleukins). Conversely, MgSO₄ had little effect on HI-induced transcription by RNA-polymerase II. De novo MgSO₄-HI affected mitochondrial function through the repression of genes of oxidative phosphorylation and many NAD-dehydrogenases. It also likely reduced protein translation by the repression of many ribosomal proteins, essentially located in synapses. All these effects appeared under the putative regulatory MgSO₄ induction of the mTORC2 Rictor coding gene. Lasting effects through Sirt1 and Frm1 could account for this epigenetic footprint.

Obstetrical characteristics and neonatal outcome according to aetiology of preterm birth: a cohort study

PURPOSE

Preterm birth (PTB) can be categorised according to aetiology into: spontaneous preterm labour (SPL), preterm prelabour rupture of membranes (PPROM), and iatrogenic (iatro) PTB. Outcomes could differ between these groups, which could be of interest in counselling. We aimed to explore differences between aetiologic groups of PTB in maternal demographics, obstetrical characteristics and management, and neonatal outcomes.

METHODS

This is a cohort study (2012-2018) in Ghent University Hospital, Belgium, of deliveries from 24 + 0 to 33 + 6 weeks. We compared perinatal demographics, management, and outcomes between the aetiologic types of PTB. Point and interval estimates for differences between aetiologic types were estimated using a Generalised Estimating Equations approach to handle clustering due to multiple gestations.

RESULTS

813 mothers and 987 neonates were included. Prevalences of different aetiologic types of PTB were similar. Maternal BMI was higher in the iatrogenic group (iatro-SPL: + 1.92 kg/m², 95% CI 1.02, 2.83; iatro-PPROM: + 2.06 kg/m², 95% CI 1.15, 2.96). There was an inversed sex ratio (0.82, 95% CI 0.65, 1.03), more growth restriction (iatro-SPL: + 22.60%, 95% CI 17.08, 28.13; iatro-PPROM: + 24.64%, 95% CI 19.44, 29.83), and a higher caesarean section rate in the iatrogenic group (iatro-SPL: + 57.23%, 95% CI 50.32, 64.13, iatro-PPROM: + 56.79%, 95% CI 50.20, 63.38) and more patients received at least one complete course of antenatal corticosteroids (iatro-SPL: + 17.60%, 95% CI 10.60, 24.60, iatro-PPROM: + 10.73%, 95% CI 4.52, 16.94). In all types of PTB, adverse neonatal outcomes had a low prevalence, except for respiratory distress syndrome. A composite of adverse neonatal outcome was more prevalent in the SPL- compared to the PPROM group, and there was less intraventricular haemorrhage in the iatrogenic group.

CONCLUSION

Additional to gestational age at birth, the aetiology of PTB is associated with neonatal outcome. More data are needed to enable individualised management and counselling in case of threatened PTB.

TRIAL REGISTRATION NUMBER

NCT03405116.

Have outcomes following extremely preterm birth improved over time?

Increased survival of infants born preterm, especially those born extremely preterm (<28 weeks' gestation), has meant that more are reaching later childhood and adulthood. As preterm birth is associated with a higher risk of neurodevelopmental deficits, the aim of this review was to determine whether or not the advances in perinatal care that led to improved survival have also had a positive impact on long-term neurodevelopment. Studies examining temporal changes in neurodevelopment are limited, and only from high-income countries. However, based on available published data, there is no definite trend of improved neurodevelopment at school age for neurosensory, cognitive, academic achievement, motor or executive function with time. Cerebral palsy rates, however, may be decreasing. More research is needed into the potential contributors for the trends observed, and also for other outcomes such as mental health and behavior.

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.

Antenatal magnesium sulfate for fetal neuroprotection: a critical appraisal and systematic review of clinical practice guidelines

Background Magnesium sulfate is an accepted intervention for fetal neuroprotection. There are some perceived differences in the international recommendations on the use magnesium sulfate for fetal neuroprotection in preterm labor. Content This systematic review analyses the available clinical guidelines for the use of magnesium sulfate for fetal neuroprotection and compares the recommendations, and assesses the quality of guidelines. This provides the consensus, differences and explores the areas for future collaborative research. We searched databases of PUBMED, EMBASE, COCHRANE, Web of Science, LILACS; and included the national and the international clinical practice guidelines. We included seven guidelines out of 227 search results. We evaluated the methodological quality of guidelines using the Appraisal of Guidelines Research and Evaluation (AGREE II) tool and systematically extracted guideline characters, recommendation and supporting evidence base. Summary Five guidelines were of high quality and two were of moderate quality. One guideline achieved more than an 80% score in all the domains of AGREE II tool. All guidelines recommend use of magnesium sulfate for fetal neuroprotection. However, there are differences in other recommendations such as upper gestational age, dose, duration, repeating treatment and use of additional tocolytics. Outlook Future guidelines should include recommendations on all aspects of magnesium sulfate therapy for fetal neuroprotection. Future research and international collaboration should focus on areas where there are no international consensual recommendations.

Takotsubo cardiomyopathy in pregnancy: a case report and literature review

BACKGROUND

Takotsubo cardiomyopathy is rare in pregnancy and is characterized by left ventricular dysfunction with apical ballooning. This transient cardiac dysfunction may affect women of childbearing age in the antepartum, intrapartum or postpartum period. Most patients respond well to medical management with resolution of cardiac dysfunction within weeks.

CASE PRESENTATION

A 35-year-old female in her second pregnancy presented with severe preeclampsia at 31 weeks of gestation. She subsequently developed severe substernal chest pain and workup showed a stress induced cardiomyopathy prior to her delivery via caesarean section. She had full recovery of her cardiac function by 12 weeks postpartum after medical management.

CONCLUSIONS

Stress induced cardiomyopathy, though rare, should be considered after acute myocardial infarction has been ruled out in gravid females presenting with acute chest pain. Management should involve a multidisciplinary team. Cardiac function recovery is common within 4 weeks although some patients may require long term heart failure management.

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.

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.