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

Cumulative effect of evidence-based practices on outcomes of preterm infants born at <29 weeks' gestational age

BACKGROUND

Extremely preterm infants born at <29 weeks' gestational age are at high risk of death or severe neurological injury. Several individual evidence-based practices have been associated with neuroprotection.

OBJECTIVE

The objective of the study was to investigate the cumulative effect of 4 evidence-based practices and their association with death and/or severe neurological injury among infants born at <29 weeks' gestational age.

STUDY DESIGN

Observational study of infants born at 23⁰-28⁶ weeks gestational age admitted to neonatal intensive care units participating in the Canadian Neonatal Network from 2015 through 2017. We evaluated 4 practices: antenatal corticosteroids, antenatal MgSO₄ for neuroprotection, deferred cord clamping ≥30 seconds, and normothermia on admission. The effect of exposure to 1, 2, 3, and all 4 evidence-based practices compared with none on death and/or severe neurological injury was assessed using multivariable logistic regression models adjusted for patient characteristics.

RESULTS

Rate of death and/or severe neurological injury was 20% (873 of 4297) and varied based on exposure to evidence-based practices: none, 34% (54 of 157); 1, 27% (171 of 626); 2, 20% (295 of 1448); 3, 18% (263 of 1448); and all 4, 14% (90 of 618). Significantly lower odds of death and/or severe neurological injury were observed with exposure to antenatal corticosteroids (adjusted odds ratio, 0.52, 95% confidence interval, 0.40-0.69) and deferred cord clamping (adjusted odds ratio, 0.81, 95% confidence interval, 0.68-0.96) but not MgSO₄ (adjusted odds ratio, 0.88, 95% confidence interval, 0.72-1.08) or normothermia (adjusted odds ratio, 0.96, 95% confidence interval, 0.79-1.16). Infants exposed to ≥2 evidence-based practices had significantly lower odds of death and/or severe neurological injury than those exposed to no evidence-based practices (adjusted odds ratio, 0.61, 95% confidence interval, 0.43-0.88).

CONCLUSION

Among infants born at <29 weeks' gestational age, exposure to at least 2 of the evidence-based practices assessed was associated with decreased odds of death and/or severe neurological injury.

High-Dose Erythropoietin in Extremely Low Gestational Age Neonates Does Not Alter Risk of Retinopathy of Prematurity

INTRODUCTION

The Preterm Erythropoietin (Epo) Neuroprotection (PENUT) Trial sought to determine the safety and efficacy of early high-dose Epo as a potential neuroprotective treatment. We hypothesized that Epo would not increase the incidence or severity of retinopathy of prematurity (ROP).

METHODS

A total of 941 infants born between 24-0/7 and 27-6/7 weeks' gestation were randomized to 1,000 U/kg Epo or placebo intravenously for 6 doses, followed by subcutaneous or sham injections of 400 U/kg Epo 3 times a week through 32 weeks post-menstrual age. In this secondary analysis of PENUT trial data, survivors were evaluated for ROP. A modified intention-to-treat approach was used to compare treatment groups. In addition, risk factors for ROP were evaluated using regression methods that account for multiples and allow for adjustment for treatment and gestational age at birth.

RESULTS

Of 845 subjects who underwent ROP examination, 503 were diagnosed with ROP with similar incidence and severity between treatment groups. Gestational age at birth, birth weight, prenatal magnesium sulfate, maternal antibiotic exposure, and presence of heart murmur at 2 weeks predicted the development of any ROP, while being on high-frequency oscillator or high-frequency jet ventilation (HFOV/HFJV) at 2 weeks predicted severe ROP.

CONCLUSION

Early high-dose Epo followed by maintenance dosing through 32 weeks does not increase the risk of any or severe ROP in extremely low gestational age neonates. Gestational age, birth weight, maternal treatment with magnesium sulfate, antibiotic use during pregnancy, and presence of a heart murmur at 2 weeks were associated with increased risk of any ROP. Treatment with HFOV/HFJV was associated with an increased risk of severe ROP.

Antenatal Magnesium Sulfate and Preeclampsia Differentially Affect Neonatal Cerebral Oxygenation

INTRODUCTION

Magnesium sulfate (MgSO4) is frequently administered for maternal and fetal neuroprotection in preeclampsia (PE) and imminent preterm birth, respectively.

OBJECTIVE

To assess whether MgSO4 affects neonatal cerebral oxygenation, blood flow, and cerebral autoregulation (CAR) during the first postnatal days independently from PE.

METHODS

148 neonates <32 weeks gestational age were included. Cerebral fractional tissue oxygen extraction (cFTOE) was extracted from a daily 2-h period, during which peak systolic blood flow velocity (PSV) and resistance index (RI) of the pericallosal artery were obtained. The percent time of impaired CAR (correlation coefficient between mean arterial blood pressure and cerebral oxygen saturation >0.5) was determined. Linear mixed models were applied.

RESULTS

MgSO4 exposure was recorded in 77 neonates. Twenty-nine neonates were born following PE. MgSO4 independently lowered cFTOE (B: -0.026, 95% CI: -0.050 to 0.002, p < 0.05) but did not affect PSV and RI. PE was associated with a lower cFTOE (B: -0.041, 95% CI: -0.067 to -0.015, p < 0.05) and a tendency towards both lower PSV (B: -4.285, 95% CI: -9.067 to 0.497, p < 0.1) and more impaired CAR (B: 4.042, 95% CI: -0.028 to 8.112, p < 0.1), which seemed to be strongly mediated by fetal brain sparing. MgSO4 did not alter CAR.

CONCLUSIONS

In contrast to fetal brain sparing in PE, MgSO4 seems to lower cFTOE by lowering cerebral oxygen demands in preterm neonates without affecting the cerebrovasculature.

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.

Sepsis: Precision-Based Medicine for Pregnancy and the Puerperium

Sepsis contributes significantly to global morbidity and mortality, particularly in vulnerable populations. Pregnant and recently pregnant women are particularly prone to rapid progression to sepsis and septic shock, with 11% of maternal deaths worldwide being attributed to sepsis. The impact on the neonate is considerable, with 1 million neonatal deaths annually attributed to maternal infection or sepsis. Pregnancy specific physiological and immunological adaptations are likely to contribute to a greater impact of infection, but current approaches to the management of sepsis are based on those developed for the non-pregnant population. Pregnancy-specific strategies are required to optimise recognition and management of these patients. We review current knowledge of the physiology and immunology of pregnancy and propose areas of research, which may advance the development of pregnancy-specific diagnostic and therapeutic approaches to optimise the care of pregnant women and their babies.

Preeclampsia: Risk Factors, Diagnosis, Management, and the Cardiovascular Impact on the Offspring

Hypertensive disorders of pregnancy affect up to 10% of pregnancies worldwide, which includes the 3%–5% of all pregnancies complicated by preeclampsia. Preeclampsia is defined as new onset hypertension after 20 weeks’ gestation with evidence of maternal organ or uteroplacental dysfunction or proteinuria. Despite its prevalence, the risk factors that have been identified lack accuracy in predicting its onset and preventative therapies only moderately reduce a woman’s risk of preeclampsia. Preeclampsia is a major cause of maternal morbidity and is associated with adverse foetal outcomes including intra-uterine growth restriction, preterm birth, placental abruption, foetal distress, and foetal death in utero. At present, national guidelines for foetal surveillance in preeclamptic pregnancies are inconsistent, due to a lack of evidence detailing the most appropriate assessment modalities as well as the timing and frequency at which assessments should be conducted. Current management of the foetus in preeclampsia involves timely delivery and prevention of adverse effects of prematurity with antenatal corticosteroids and/or magnesium sulphate depending on gestation. Alongside the risks to the foetus during pregnancy, there is also growing evidence that preeclampsia has long-term adverse effects on the offspring. In particular, preeclampsia has been associated with cardiovascular sequelae in the offspring including hypertension and altered vascular function.

Decision-making around resuscitation of extremely preterm infants in the Philippines: A consensus guideline

While the vast majority of preterm births globally occur in low- and middle-income countries, existing published guidelines relating to the decision-making and resuscitation of extremely preterm infants (EPIs) largely focus on high-income countries. In 2018-2019, a working group of the Philippine Society of Newborn Medicine aimed to develop the first national guideline relating to the care of EPIs. The working group reviewed data on the outcomes of EPIs in the Philippines, surveyed paediatricians and neonatologists in the Philippines about current practice and held a consensus workshop. This paper describes the guideline development process and presents a summary of the guidelines. The national guidelines endorse consistency in decision-making. Health professionals should take into consideration the views and wishes of the infant's parents and the availability of resources to treat the newborn infant. Active management would be appropriate to provide for potentially viable preterm infants at moderate to high risk of poor outcomes, where parents have expressed their wish for this management (and where there are resources available to provide this treatment). For such infants, where parents have expressed their wish to withhold active management, palliative management would also be appropriate to provide. The guideline endorses a grey zone for neonatal resuscitation from approximately 24 to 28 weeks' gestation in the Philippines, reflecting the context for resuscitation in low- and middle-income countries. Disparities in resource availability are themselves an ethical concern for neonatologists and should be a stimulus for advocacy and improvements in health-care delivery.

Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry Number 015/025, February 2019) - Part 2 with Recommendations on the Tertiary Prevention of Preterm Birth and the Management of Preterm Premature Rupture of Membranes

Aims This is an official guideline of the German Society for Gynecology and Obstetrics (DGGG), the Austrian Society for Gynecology and Obstetrics (ÖGGG) and the Swiss Society for Gynecology and Obstetrics (SGGG). The aim of this guideline is to improve the prediction, prevention and management of preterm birth based on evidence obtained from recently published scientific literature, the experience of the members of the guideline commission and the views of self-help groups. Methods The members of the participating medical societies and organizations developed Recommendations and Statements based on the international literature. The Recommendations and Statements were adopted following a formal consensus process (structured consensus conference with neutral moderation, voting done in writing using the Delphi method to achieve consensus). Recommendations Part 2 of this short version of the guideline presents Statements and Recommendations on the tertiary prevention of preterm birth and the management of preterm premature rupture of membranes.

Coadministration of the prostaglandin F2α receptor antagonist preterm labour drug candidate OBE022 with magnesium sulfate, atosiban, nifedipine and betamethasone

AIMS

To investigate presence or absence of clinically relevant drug interactions (pharmacokinetic and safety/tolerability) of OBE022 with standard-of-care medicines for preterm labour, enabling coadministration and further clinical development.

METHODS

Part A: open-label, randomized, 3-period crossover assessing coadministration of single doses of OBE022 (1100 mg) and MgSO4 . Part B: open-label, single-sequence crossover assessing the interactions following administration of OBE022 (1000 mg/day) at steady state coadministered with single doses of atosiban, nifedipine and betamethasone. Twenty-five healthy nonpregnant women of reproductive age were enrolled (Part A: n = 12; Part B: n = 13).

RESULTS

OBE022, alone or in combination with standard-of-care medications, was well tolerated. Headache and dizziness were the most frequently reported adverse events; dizziness occurred more often with the nifedipine/OBE022 combination. There were no clinically significant pharmacokinetic interactions when coadministered with MgSO4 . Co-administration had no notable effect on atosiban exposure. Atosiban reduced exposure to OBE002 (peak concentration [Cmax ] 22%, area under the concentration-time curve [AUC] 19%). Coadministration with betamethasone slightly increased betamethasone exposure (Cmax  + 18%, AUC +27%) and OBE002 exposure (Cmax  + 35%, AUC +15%). These changes were not considered clinically significant. Coadministration with nifedipine slightly increased OBE002 exposure (Cmax  + 29%, AUC +24%) and markedly increased nifedipine exposure (Cmax by 2-fold and AUC by 2-fold), which may be clinically significant.

CONCLUSIONS

The use of OBE022, a PGF2α antagonist prodrug, in combination with standard-of-care medicines may provide new treatment alternatives for preterm labour. All tested combinations were well tolerated. Nifedipine doses could potentially be reduced or staggered when coadministered with OBE022.

Neuroprotection from acute brain injury in preterm infants

Infants born at ≤32+6 weeks gestation are at higher risk for intracranial ischemic and hemorrhagic injuries, which often occur in the first 72 hours postbirth. Antenatal strategies to reduce the incidence of acute brain injuries include administering maternal corticosteroids and prompt antibiotic treatment for chorioamnionitis. Perinatal strategies include delivery within a tertiary centre, delayed cord clamping, and preventing hypothermia. Postnatal strategies include empiric treatment with antibiotics when chorioamnionitis is suspected, the cautious use of inotropes, the avoidance of blood PCO2 fluctuation, and neutral head positioning. Clinicians should be aware of the policies and procedures that, especially when combined, can provide neuroprotection for preterm infants.

Magnesium induces preconditioning of the neonatal brain via profound mitochondrial protection

Magnesium sulphate (MgSO4) given to women in preterm labor reduces cerebral palsy in their offspring but the mechanism behind this protection is unclear, limiting its effective, safe clinical implementation. Previous studies suggest that MgSO4 is not neuroprotective if administered during or after the insult, so we hypothesised that MgSO4 induces preconditioning in the immature brain. Therefore, we administered MgSO4 at various time-points before/after unilateral hypoxia-ischemia (HI) in seven-day-old rats. We found that MgSO4 treatment administered as a bolus between 6 days and 12 h prior to HI markedly reduced the brain injury, with maximal protection achieved by 1.1 mg/g MgSO4 administered 24 h before HI. As serum magnesium levels returned to baseline before the induction of HI, we ascribed this reduction in brain injury to preconditioning. Cerebral blood flow was unaffected, but mRNAs/miRNAs involved in mitochondrial function and metabolism were modulated by MgSO4. Metabolomic analysis (H+-NMR) disclosed that MgSO4 attenuated HI-induced increases in succinate and prevented depletion of high-energy phosphates. MgSO4 pretreatment preserved mitochondrial respiration, reducing ROS production and inflammation after HI. Therefore, we propose that MgSO4 evokes preconditioning via induction of mitochondrial resistance and attenuation of inflammation.

Reduced Neurosteroid Exposure Following Preterm Birth and Its' Contribution to Neurological Impairment: A Novel Avenue for Preventative Therapies

Children born preterm are at an increased risk of developing cognitive problems and neuro-behavioral disorders such as attention deficit hyperactivity disorder (ADHD) and anxiety. Whilst neonates born at all gestational ages, even at term, can experience poor cognitive outcomes due to birth-complications such as birth asphyxia, it is becoming widely known that children born preterm in particular are at significant risk for learning difficulties with an increased utilization of special education resources, when compared to their healthy term-born peers. Additionally, those born preterm have evidence of altered cerebral myelination with reductions in white matter volumes of the frontal cortex, hippocampus and cerebellum evident on magnetic resonance imaging (MRI). This disruption to myelination may underlie some of the pathophysiology of preterm-associated brain injury. Compared to a fetus of the same post-conceptional age, the preterm newborn loses access to in utero factors that support and promote healthy brain development. Furthermore, the preterm ex utero environment is hostile to the developing brain with a myriad of environmental, biochemical and excitotoxic stressors. Allopregnanolone is a key neuroprotective fetal neurosteroid which has promyelinating effects in the developing brain. Preterm birth leads to an abrupt loss of the protective effects of allopregnanolone, with a dramatic drop in allopregnanolone concentrations in the preterm neonatal brain compared to the fetal brain. This occurs in conjunction with reduced myelination of the hippocampus, subcortical white matter and cerebellum; thus, damage to neurons, astrocytes and especially oligodendrocytes of the developing nervous system can occur in the vulnerable developmental window prior to term as a consequence reduced allopregnanolone. In an effort to prevent preterm-associated brain injury a number of therapies have been considered, but to date, other than antenatal magnesium sulfate and corticosteroid therapy, none have become part of standard clinical care for vulnerable infants. Therefore, there remains an urgent need for improved therapeutic options to prevent brain injury in preterm neonates. The actions of the placentally derived neurosteroid allopregnanolone on GABAA receptor signaling has a major role in late gestation neurodevelopment. The early loss of this intrauterine neurotrophic support following preterm birth may be pivotal to development of neurodevelopmental morbidity. Thus, restoring the in utero neurosteroid environment for preterm neonates may represent a new and clinically feasible treatment option for promoting better trajectories of myelination and brain development, and therefore reducing neurodevelopmental disorders in children born preterm.

Glutamate Transport and Preterm Brain Injury

Preterm birth complications are the leading cause of child death worldwide and a top global health priority. Among the survivors, the risk of life-long disabilities is high, including cerebral palsy and impairment of movement, cognition, and behavior. Understanding the molecular mechanisms of preterm brain injuries is at the core of future healthcare improvements. Glutamate excitotoxicity is a key mechanism in preterm brain injury, whereby the accumulation of extracellular glutamate damages the delicate immature oligodendrocytes and neurons, leading to the typical patterns of injury seen in the periventricular white matter. Glutamate excitotoxicity is thought to be induced by an interaction between environmental triggers of injury in the perinatal period, particularly cerebral hypoxia-ischemia and infection/inflammation, and developmental and genetic vulnerabilities. To avoid extracellular build-up of glutamate, the brain relies on rapid uptake by sodium-dependent glutamate transporters. Astrocytic excitatory amino acid transporter 2 (EAAT2) is responsible for up to 95% of glutamate clearance, and several lines of evidence suggest that it is essential for brain functioning. While in the adult EAAT2 is predominantly expressed by astrocytes, EAAT2 is transiently upregulated in the immature oligodendrocytes and selected neuronal populations during mid-late gestation, at the peak time for preterm brain injury. This developmental upregulation may interact with perinatal hypoxia-ischemia and infection/inflammation and contribute to the selective vulnerability of the immature oligodendrocytes and neurons in the preterm brain. Disruption of EAAT2 may involve not only altered expression but also impaired function with reversal of transport direction. Importantly, elevated EAAT2 levels have been found in the reactive astrocytes and macrophages of human infant post-mortem brains with severe white matter injury (cystic periventricular leukomalacia), potentially suggesting an adaptive mechanism against excitotoxicity. Interestingly, EAAT2 is suppressed in animal models of acute hypoxic-ischemic brain injury at term, pointing to an important and complex role in newborn brain injuries. Enhancement of EAAT2 expression and transport function is gathering attention as a potential therapeutic approach for a variety of adult disorders and awaits exploration in the context of the preterm brain injuries.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome - 2019 Update

As management of respiratory distress syndrome (RDS) advances, clinicians must continually revise their current practice. We report the fourth update of "European Guidelines for the Management of RDS" by a European panel of experienced neonatologists and an expert perinatal obstetrician based on available literature up to the end of 2018. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, need for appropriate maternal transfer to a perinatal centre and timely use of antenatal steroids. Delivery room management has become more evidence-based, and protocols for lung protection including initiation of CPAP and titration of oxygen should be implemented immediately after birth. Surfactant replacement therapy is a crucial part of management of RDS, and newer protocols for its use recommend early administration and avoidance of mechanical ventilation. Methods of maintaining babies on non-invasive respiratory support have been further developed and may cause less distress and reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation using caffeine and, if necessary, postnatal steroids are also important considerations. Protocols for optimising general care of infants with RDS are also essential with good temperature control, careful fluid and nutritional management, maintenance of perfusion and judicious use of antibiotics all being important determinants of best outcome.

Lack of Evidence for Time or Dose Relationship between Antenatal Magnesium Sulfate and Intestinal Injury in Extremely Preterm Neonates

BACKGROUND

Recent studies reported conflicting results on the relationship between antenatal magnesium sulfate (MgSO4) exposure and neonatal intestinal injury. Most studies have not assessed MgSO4 exposure quantitatively and none reported the exposure timing.

OBJECTIVES

The aim of this work was to assess whether there is a temporal or dose-dependent relationship between antenatal MgSO4 exposure and intestinal injury in extremely preterm neonates.

METHODS

A retrospective study was made of inborn neonates with gestational age ≤28 weeks and/or birth weights ≤1,000 g. Primary outcomes included necrotizing enterocolitis (NEC), spontaneous intestinal perforation (SIP), and/or death prior to discharge or in the first 2 weeks of life. Outcome comparisons were made based on the timing of MgSO4 exposure, within 7 days (Mg7D) or within 3 days (Mg3D) of birth. Total cumulative doses for the Mg3D group were also computed.

RESULTS

A total of 302 neonates were included, 210 in the Mg7D group, out of whom 179 (85.2%) constituted the Mg3D group. There were no differences noted when comparing MgSO4 exposure timing and the likelihood of NEC, SIP, and/or death. This remained the same for subgroup analysis of neonates < 26 weeks' gestation. Each 10-g increase in MgSO4 cumulative dose correlated with a decrease in SIP/NEC/death by 18.9% prior to discharge and by 21.9% in the first 2 weeks of life. Small for gestational age (SGA) was a potential effect modifier by a likelihood ratio test with p = 0.07.

CONCLUSIONS

Antenatal MgSO4 exposure in extremely preterm neonates was not associated with an increased risk of intestinal injury or death, and might have reduced these complications in a dose-dependent manner in our study. This protective effect was more noticeable in SGA neonates.

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.

Maternal Magnesium Sulfate Supplementation in a Pre-Farrow Diet Improves Factors Important for Piglet Viability

Piglet hypoxia during farrowing is common and can lead to increased stillbirth rates, reduced piglet vitality, and an increased risk of preweaning mortality. Magnesium sulfate (MgSO₄) has successfully been used as a neuroprotectant and readily crosses the placenta in humans. Based on this human data, the aim of this study was to determine if maternal dietary supplementation with MgSO₄ prior to farrowing would reduce the impact of piglet hypoxia during the peri-natal period. Five days prior to farrowing, Large White × Landrace sows were fed either standard lactation sow diet (Cont; n = 30) or lactation diet supplemented to deliver 21 g/day MgSO₄ (Mg; n = 31). There was no effect of treatment on the percentage of stillborn piglets (p > 0.05). However, Mg piglets tended to have higher vitality scores immediately after birth (p < 0.10), were quicker to suck, and had higher day one blood glucose concentrations when compared with Cont piglets (p < 0.05). Furthermore, hypoxic piglets born to Cont sows did not gain weight from birth to 24 h, but Mg piglets did (p < 0.05), suggesting improved colostrum ingestion. In conclusion, MgSO₄ may reduce the negative impacts of birth hypoxia, improving piglet vitality, and colostrum intake during the peri-natal period.

Autism Spectrum Disorder and Neonatal Serum Magnesium Levels in Preterm Infants

Premature birth is associated with increased risk of autism spectrum disorder. Antenatal maternal magnesium administration is known to reduce subsequent risk of cerebral palsy including among premature infants, suggesting a potentially broader neuroprotective role for magnesium. Our objective was to determine whether magnesium could be protective against autism spectrum disorders in premature infants. A cohort of 4855 preterm children was identified, magnesium levels from 24 to 48 hours of life recorded, and subsequent autism spectrum disorder status determined. Adjusted relative risk of autism spectrum disorder with each 1 mg/dL increase in neonatal magnesium level was 1.15 (95% confidence interval: 0.86-1.53). Analysis of variance indicated that magnesium levels varied by gestational age and maternal antenatal magnesium supplementation, but not autism spectrum disorder status (F_1,4824 = 1.43, P = .23). We found that neonatal magnesium levels were not associated with decreased autism spectrum disorder risk. Future research into autism spectrum disorder risks and treatments in premature infants is needed.

Antenatal prevention of cerebral palsy and childhood disability: is the impossible possible?

This review covers our current knowledge of the causes of perinatal brain injury leading to cerebral palsy-like outcomes, and argues that much of this brain damage is preventable. We review the experimental evidence that there are treatments that can be safely administered to women in late pregnancy that decrease the likelihood and extent of perinatal brain damage that occurs because of acute and severe hypoxia that arises during some births, and the additional impact of chronic fetal hypoxia, infection, inflammation, growth restriction and preterm birth. We discuss the types of interventions required to ameliorate or even prevent apoptotic and necrotic cell death, and the vulnerability of all the major cell types in the brain (neurons, astrocytes, oligodendrocytes, microglia, cerebral vasculature) to hypoxia/ischaemia, and whether a pan-protective treatment given to the mother before birth is a realistic prospect.

Neonatal interventions for preventing cerebral palsy: an overview of Cochrane Systematic Reviews

BACKGROUND

Cerebral palsy is an umbrella term that encompasses disorders of movement and posture attributed to non-progressive disturbances occurring in the developing foetal or infant brain. As there are diverse risk factors and aetiologies, no one strategy will prevent cerebral palsy. Therefore, there is a need to systematically consider all potentially relevant interventions for prevention.

OBJECTIVES

PrimaryTo summarise the evidence from Cochrane Systematic Reviews regarding effects of neonatal interventions for preventing cerebral palsy (reducing cerebral palsy risk).SecondaryTo summarise the evidence from Cochrane Systematic Reviews regarding effects of neonatal interventions that may increase cerebral palsy risk.

METHODS

We searched the Cochrane Database of Systematic Reviews (27 November 2016) for reviews of neonatal interventions reporting on cerebral palsy. Two review authors assessed reviews for inclusion, extracted data, and assessed review quality (using AMSTAR and ROBIS) and quality of the evidence (using the GRADE approach). Reviews were organised by topic; findings were summarised in text and were tabulated. Interventions were categorised as effective (high-quality evidence of effectiveness); possibly effective (moderate-quality evidence of effectiveness); ineffective (high-quality evidence of harm); probably ineffective (moderate-quality evidence of harm or lack of effectiveness); and no conclusions possible (low- to very low-quality evidence).

MAIN RESULTS

Forty-three Cochrane Reviews were included. A further 102 reviews pre-specified the outcome cerebral palsy, but none of the included randomised controlled trials (RCTs) reported this outcome. Included reviews were generally of high quality and had low risk of bias, as determined by AMSTAR and ROBIS. These reviews involved 454 RCTs; data for cerebral palsy were available from 96 (21%) RCTs involving 15,885 children. Review authors considered interventions for neonates with perinatal asphyxia or with evidence of neonatal encephalopathy (3); interventions for neonates born preterm and/or at low or very low birthweight (33); and interventions for other specific groups of 'at risk' neonates (7). Quality of evidence (GRADE) ranged from very low to high.Interventions for neonates with perinatal asphyxia or with evidence of neonatal encephalopathyEffective interventions: high-quality evidence of effectivenessResearchers found a reduction in cerebral palsy following therapeutic hypothermia versus standard care for newborns with hypoxic ischaemic encephalopathy (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.54 to 0.82; seven trials; 881 children).No conclusions possible: very low-quality evidenceOne review observed no clear differences in cerebral palsy following therapeutic hypothermia versus standard care.Interventions for neonates born preterm and/or at low or very low birthweightPossibly effective interventions: moderate-quality evidence of effectivenessResearchers found a reduction in cerebral palsy with prophylactic methylxanthines (caffeine) versus placebo for endotracheal extubation in preterm infants (RR 0.54, 95% CI 0.32 to 0.92; one trial; 644 children).Probably ineffective interventions: moderate-quality evidence of harmResearchers reported an increase in cerebral palsy (RR 1.45, 95% CI 1.06 to 1.98; 12 trials; 1452 children) and cerebral palsy in assessed survivors (RR 1.50, 95% CI 1.13 to 2.00; 12 trials; 959 children) following early (at less than eight days of age) postnatal corticosteroids versus placebo or no treatment for preventing chronic lung disease in preterm infants.Probably ineffective interventions: moderate-quality evidence of lack of effectivenessTrial results showed no clear differences in cerebral palsy following ethamsylate versus placebo for prevention of morbidity and mortality in preterm or very low birthweight infants (RR 1.13, 95% CI 0.64 to 2.00; three trials, 532 children); volume expansion versus no treatment (RR 0.76, 95% CI 0.48 to 1.20; one trial; 604 children); gelatin versus fresh frozen plasma (RR 0.94, 95% CI 0.52 to 1.69; one trial, 399 children) for prevention of morbidity and mortality in very preterm infants; prophylactic indomethacin versus placebo for preventing mortality and morbidity in preterm infants (RR 1.04, 95% CI 0.77 to 1.40; four trials; 1372 children); synthetic surfactant versus placebo for respiratory distress syndrome in preterm infants (RR 0.76, 95% CI 0.55 to 1.05; five trials; 1557 children); or prophylactic phototherapy versus standard care (starting phototherapy when serum bilirubin reached a pre-specified level) for preventing jaundice in preterm or low birthweight infants (RR 0.96, 95% CI 0.50 to 1.85; two trials; 756 children).No conclusions possible: low- to very low-quality evidenceNo clear differences in cerebral palsy were observed with interventions assessed in 21 reviews.Interventions for other specific groups of 'at risk' neonatesNo conclusions possible: low- to very low-quality evidenceReview authors observed no clear differences in cerebral palsy with interventions assessed in five reviews.

AUTHORS' CONCLUSIONS

This overview summarises evidence from Cochrane Systematic Reviews regarding effects of neonatal interventions on cerebral palsy, and can be used by researchers, funding bodies, policy makers, clinicians, and consumers to aid decision-making and evidence translation. To formally assess other benefits and/or harms of included interventions, including impact on risk factors for cerebral palsy, review of the included Reviews is recommended.Therapeutic hypothermia versus standard care for newborns with hypoxic ischaemic encephalopathy can prevent cerebral palsy, and prophylactic methylxanthines (caffeine) versus placebo for endotracheal extubation in preterm infants may reduce cerebral palsy risk. Early (at less than eight days of age) postnatal corticosteroids versus placebo or no treatment for preventing chronic lung disease in preterm infants may increase cerebral palsy risk.Cerebral palsy is rarely identified at birth, has diverse risk factors and aetiologies, and is diagnosed in approximately one in 500 children. To date, only a small proportion of Cochrane Systematic Reviews assessing neonatal interventions have been able to report on this outcome. There is an urgent need for long-term follow-up of RCTs of such interventions addressing risk factors for cerebral palsy (through strategies such as data linkage with registries) and for consideration of the use of relatively new interim assessments (including the General Movements Assessment). Such RCTs must be rigorous in their design and must aim for consistency in cerebral palsy outcome measurement and reporting to facilitate pooling of data and thus to maximise research efforts focused on prevention.

Pregnancy as a valuable period for preventing hypoxia-ischemia brain damage

Neonatal brain Hypoxia-Ischemia (HI) is one of the major causes of infant mortality and lifelong neurological disabilities. The knowledge about the physiopathological mechanisms involved in HI lesion have increased in recent years, however these findings have not been translated into clinical practice. Current therapeutic approaches remain limited; hypothermia, used only in term or near-term infants, is the golden standard. Epidemiological evidence shows a link between adverse prenatal conditions and increased risk for diseases, health problems, and psychological outcomes later in life, what makes pregnancy a relevant period for preventing future brain injury. Here, we review experimental literature regarding preventive interventions used during pregnancy, i.e., previous to the HI injury, encompassing pharmacological, nutritional and/or behavioral strategies. Literature review used PubMed database. A total of forty one studies reported protective properties of maternal treatments preventing perinatal hypoxia-ischemia injury in rodents. Pharmacological agents and dietary supplementation showed mainly anti-excitotoxicity, anti-oxidant or anti-apoptotic properties. Interestingly, maternal preconditioning, physical exercise and environmental enrichment seem to engage the same referred mechanisms in order to protect neonatal brain against injury. This construct must be challenged by further studies to clearly define the main mechanisms responsible for neuroprotection to be explored in experimental context, as well as to test their potential in clinical settings.

Effect of nifedipine and atosiban on perinatal brain injury: secondary analysis of the APOSTEL-III trial

OBJECTIVE

Brain injury in neonates born prematurely is associated strongly with poor neurodevelopmental outcome. The aim of this study was to evaluate whether tocolysis with nifedipine or atosiban in women with threatened preterm birth can reduce the incidence of overall brain injury in neonates born prematurely.

METHODS

This was a secondary analysis of the APOSTEL-III trial (Dutch Clinical Trial Registry, no. NTR2947), a randomized clinical trial in which women with threatened preterm labor between 25 and 34 weeks of gestation were allocated to treatment with nifedipine or atosiban. In this secondary analysis, women delivered at ≤ 32 weeks of gestational age in the two main contributing centers were included. Primary outcome was the presence of neonatal brain injury, which was defined as presence of abnormalities on ultrasound investigation and classified into mild and severe. To evaluate type and severity of brain injury, all neonatal ultrasounds performed during neonatal intensive and medium care admission were analyzed. To test the robustness of our results, a sensitivity analysis was performed assessing differences in baseline or known risk factors for brain injury.

RESULTS

A total of 117 neonates (from 102 women) were studied, of which 51 had been exposed to nifedipine and 66 to atosiban. Brain injury was observed in 22 (43.1%) neonates in the nifedipine group compared with 37 (56.1%) in the atosiban group (OR, 0.60; 95% CI, 0.29-1.24). Presence of mild brain injury was comparable between the nifedipine (33.3%) and atosiban (48.5%) groups (OR, 0.53; 95% CI, 0.25-1.13). Severe brain injury was also comparable between the groups, observed in 9.8% of neonates in the nifedipine vs 7.6% of those in the atosiban group (OR, 1.33; 95% CI, 0.36-4.85). Intraventricular hemorrhage (≥ Grade I) was the most frequently seen ultrasound abnormality, observed in 18 (35.3%) neonates in the nifedipine group vs 25 (37.9%) in the atosiban group (OR, 0.90; 95% CI, 0.42-1.91). The sensitivity analysis, with adjustment for maternal age and gestational age at randomization, showed no statistical difference between the groups for presence of brain injury (OR, 0.58; 95% CI, 0.27-1.27).

CONCLUSION

In children born before 32 weeks of gestation after the use of tocolytics, the prevalence of brain injury was high. No significant differences were found with respect to overall brain injury between neonates exposed to nifedipine and those exposed to atosiban. However, as this study was a secondary analysis of the APOSTEL III trial, it was underpowered for brain injury. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

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.

Telomere Homeostasis: Interplay with Magnesium

Telomere biology, a key component of the hallmarks of ageing, offers insight into dysregulation of normative ageing processes that accompany age-related diseases such as cancer. Telomere homeostasis is tightly linked to cellular metabolism, and in particular with mitochondrial physiology, which is also diminished during cellular senescence and normative physiological ageing. Inherent in the biochemistry of these processes is the role of magnesium, one of the main cellular ions and an essential cofactor in all reactions that use ATP. Magnesium plays an important role in many of the processes involved in regulating telomere structure, integrity and function. This review explores the mechanisms that maintain telomere structure and function, their influence on circadian rhythms and their impact on health and age-related disease. The pervasive role of magnesium in telomere homeostasis is also highlighted.

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.

Chorioamnionitis, IL-17A, and fetal origins of neurologic disease

The Centers for Disease Control and Prevention estimate that 1 in 323 infants have cerebral palsy. Highly correlated to intrauterine infection and inflammation, the incidence of cerebral palsy has remained constant over the last few decades despite significant advances in neonatal intensive care including improved ventilator techniques, surfactant therapy, maternal steroid administration, and use of intrapartum empiric antimicrobials. Recent advances in our understanding of immune responses to infection and inflammation have identified the cytokine IL-17A as a crucial component of early proinflammatory mediators that cause brain injury associated with neurologic impairment. Remarkably, maternal inflammatory responses to in utero inflammation and infection can also lead to potentially debilitating neurologic conditions in the offspring, which often become clinically apparent during childhood and/or early adulthood. This review details the role of IL-17A in fetal and maternal proinflammatory responses that lead to fetal brain injury and neurologic sequelae, including cerebral palsy. Recent findings regarding the role of maternal inflammatory responses in the development of childhood and adult neurologic conditions, such as autism, schizophrenia, and multiple sclerosis, will also be highlighted.

Long-term impact of intrauterine neuroinflammation and treatment with magnesium sulphate and betamethasone: Sex-specific differences in a preterm labor murine model

Preterm infants are at significantly increased risk for lifelong neurodevelopmental disability with male offspring disproportionately affected. Corticosteroids (such as betamethasone) and magnesium sulphate (MgSO₄) are administered to women in preterm labor to reduce neurologic morbidity. Despite widespread use of MgSO₄ in clinical practice, its effects on adult offspring are not well known nor have sex-specific differences in therapeutic response been explored. The objective of our study was to examine the long-term effects of perinatal neuroinflammation and the effectiveness of prenatal MgSO₄/betamethasone treatments between males and females in a murine model via histologic and expression analyses. Our results demonstrate that male but not female offspring exposed to intrauterine inflammation demonstrated impaired performance in neurodevelopmental testing in early life assessed via negative geotaxis, while those exposed to injury plus treatment fared better. Histologic analysis of adult male brains identified a significant reduction in hippocampal neural density in the injured group compared to controls. Evaluation of key neural markers via qRT-PCR demonstrated more profound differences in gene expression in adult males exposed to injury and treatment compared to female offspring, which largely showed resistance to injury. Prenatal treatment with MgSO₄/betamethasone confers long-term benefits beyond cerebral palsy prevention with sex-specific differences in response.

How does preeclampsia affect neonates? Highlights in the disease's immunity

INTRODUCTION

Preeclampsia (PE) is the primary obstetrical cause in one of the four perinatal deaths. Although the etiology and pathogenesis of preeclampsia is not fully known, a proinflammatory immune state prevails and can disrupt fetal hematopoiesis. Some of the effects on the newborn include neonatal thrombocytopenia, neutropenia, a reduction in T regulatory cells, and an increased cytotoxic natural killer cell profile.

METHODS

Electronic databases were searched, and defined criteria were applied to select articles for review. The review covered literature on the effects on neonatal due to maternal preeclampsia, fetal outcomes, and new treatments in research aimed at reducing morbidity and mortality of the disease.

DISCUSSION

The cytotoxic environment present in PE affects the development of fetal cell lineages. Neutropenia is observed in 50% of neonates and is correlated with mortality, although its treatment is not well-established. The enhancement in erythropoietin and the hypoxic setting present in the disease can also lead to thrombocytopenia. Per partum management includes platelet transfusion in order to avoid severe complications such as intraventricular hemorrhage. Regarding other cell lines, a cytotoxic profile is observed to be reflecting the milieu present in the mothers' bloodstream. This disruption alters the immune system response into a proinflammatory profile and can be correlated to neonatal necrotizing enterocolitis. An antiangiogenic environment is also part of the preeclampsia presentation and can be responsible for the enhancement of bronchopulmonary dysplasia observed in this population. Meanwhile, the reduction in angiogenic factors, such as vascular endothelial growth factor (VEGF), can be a protective mechanism for retinopathy of prematurity. Studies of the long-term effects of these observations are lacking, but lower neurodevelopmental scores and a higher cardiovascular risk are noted. New treatments in research propose a prevention of the disease during gestation in order to reduce the effects more efficiently in the fetus. Phosphodiesterase inhibitors, endothelin 1 receptor antagonists and manipulation of heme oxygenase-1 enzyme pathway are possible therapeutic alternatives. This review summarizes the current understanding of how preeclampsia affects neonates. As a conclusion, further studies are needed to build up a guideline to manage those effects. A research agenda is proposed.

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.

Racial/Ethnic Disparities in Morbidity and Mortality for Preterm Neonates Admitted to a Tertiary Neonatal Intensive Care Unit

OBJECTIVE

The objective of this study was to assess whether in-hospital morbidity or mortality differed by race/ethnicity for preterm neonates admitted to the neonatal intensive care unit (NICU).

STUDY DESIGN

In a retrospective cohort study, preterm infants, < 37 weeks, were admitted to the NICU from 1994 to 2009. Exclusions included structural anomalies and aneuploidy. Primary outcome was in-hospital mortality (IHM). Secondary outcomes were respiratory distress syndrome (RDS), interventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP). Sub-analysis of very preterm (VPT) infants, < 28 weeks, was performed. Five racial/ethnic groups (REGs) were compared: White, Black, Hispanic, Asian, and Mixed. Associations were modeled by logistic regression. White neonates (WNs) were the referent group. Unadjusted and adjusted odds ratios and 95% confidence intervals for remaining REGs were reported. p value was significant at 5% for overall tests and at Bonferroni-corrected level < 0.0125 for between-race comparisons with WNs.

RESULTS

Four thousand nine hundred fifty-five preterm neonates were identified; 153 were excluded leaving 4802 for analysis. After controlling covariates that were chosen a priori, there was no difference across REGs for IHM (all between-race comparison p values > 0.0125). There was a significant difference in RDS among Black neonates (BNs) (aOR 0.57, 95% CI 0.45-0.73; p < 0.001) and Hispanic neonates (HNs) (aOR 0.67, 95% CI 0.50-0.89; p = 0.005) compared to WNs. The risk of ROP was significantly different across REGs with HNs having a 70% increase in ROP (aOR 1.70, 95% CI 1.15-2.49; p = 0.008) and Mixed neonates (MNs) experiencing a 55% reduction (aOR 0.45, 95% CI 0.29-0.68; p < 0.001) compared to WNs. There was no difference in IVH or NEC across REGs (all p values > 0.0125). In the VPT cohort sub-analysis, BNs experienced a significant 59% reduction in IHM compared to WNs (BNs aOR 0.41, 95% CI 0.22-0.73; p = 0.003). MNs experienced a 46% reduction in ROP compared to WNs (aOR 0.54, 95% CI 0.35-0.81; p = 0.004). There was no difference in RDS, IVH, or NEC in very preterm infants across REGs (all between comparison p values > 0.0125).

CONCLUSION

In preterm neonates, in-hospital mortality does not significantly differ across racial and ethnic groups. However, in very preterm infants, in-hospital mortality for Black neonates is improved. There are morbidity differences (RDS, ROP) seen among racial/ethnic groups.

Effect of Therapeutic Hypothermia Initiated After 6 Hours of Age on Death or Disability Among Newborns With Hypoxic-Ischemic Encephalopathy: A Randomized Clinical Trial

Importance

Hypothermia initiated at less than 6 hours after birth reduces death or disability for infants with hypoxic-ischemic encephalopathy at 36 weeks' or later gestation. To our knowledge, hypothermia trials have not been performed in infants presenting after 6 hours.

Objective

To estimate the probability that hypothermia initiated at 6 to 24 hours after birth reduces the risk of death or disability at 18 months among infants with hypoxic-ischemic encephalopathy.

Design, Setting, and Participants

A randomized clinical trial was conducted between April 2008 and June 2016 among infants at 36 weeks' or later gestation with moderate or severe hypoxic-ischemic encephalopathy enrolled at 6 to 24 hours after birth. Twenty-one US Neonatal Research Network centers participated. Bayesian analyses were prespecified given the anticipated limited sample size.

Interventions

Targeted esophageal temperature was used in 168 infants. Eighty-three hypothermic infants were maintained at 33.5°C (acceptable range, 33°C-34°C) for 96 hours and then rewarmed. Eighty-five noncooled infants were maintained at 37.0°C (acceptable range, 36.5°C-37.3°C).

Main Outcomes and Measures

The composite of death or disability (moderate or severe) at 18 to 22 months adjusted for level of encephalopathy and age at randomization.

Results

Hypothermic and noncooled infants were term (mean [SD], 39 [2] and 39 [1] weeks' gestation, respectively), and 47 of 83 (57%) and 55 of 85 (65%) were male, respectively. Both groups were acidemic at birth, predominantly transferred to the treating center with moderate encephalopathy, and were randomized at a mean (SD) of 16 (5) and 15 (5) hours for hypothermic and noncooled groups, respectively. The primary outcome occurred in 19 of 78 hypothermic infants (24.4%) and 22 of 79 noncooled infants (27.9%) (absolute difference, 3.5%; 95% CI, -1% to 17%). Bayesian analysis using a neutral prior indicated a 76% posterior probability of reduced death or disability with hypothermia relative to the noncooled group (adjusted posterior risk ratio, 0.86; 95% credible interval, 0.58-1.29). The probability that death or disability in cooled infants was at least 1%, 2%, or 3% less than noncooled infants was 71%, 64%, and 56%, respectively.

Conclusions and Relevance

Among term infants with hypoxic-ischemic encephalopathy, hypothermia initiated at 6 to 24 hours after birth compared with noncooling resulted in a 76% probability of any reduction in death or disability, and a 64% probability of at least 2% less death or disability at 18 to 22 months. Hypothermia initiated at 6 to 24 hours after birth may have benefit but there is uncertainty in its effectiveness.

Trial Registration

clinicaltrials.gov Identifier: NCT00614744.

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.

Preventing cerebral palsy in preterm labour: a multiorganisational quality improvement approach to the adoption and spread of magnesium sulphate for neuroprotection

Magnesium sulphate has been demonstrated to be an effective neuroprotectant for babies delivered prematurely (under 37 weeks' gestational age). Antenatal administration reduces infant mortality and cerebral palsy (CP); however, uptake in the UK has been significantly lower than other countries. A quality improvement (QI) project (PReventing Cerebral palsy in Pre Term labour (PReCePT)) was carried out in the West of England, UK, to raise awareness of evidence and to improve the uptake of magnesium sulphate as neuroprotectant in preterm deliveries. Five National Health Service (NHS) Trusts and the West of England Academic Health Science Network participated in the QI project. The project was underpinned by a multifaceted QI approach that included: patient and clinical coproduction of resources; recruitment of clinical champions to support the local microsystems and create a stimulating/supporting environment for change; Plan, Do, Study, Act cycles; training for over 600 NHS staff and awareness raising and strategic influencing of key leaders. A baseline audit and regular measurement of the number of eligible women receiving magnesium sulphate was undertaken at each hospital site, and the overall programme was evaluated using data from an international benchmarking organisation for neonatal care outcomes-the Vermont Oxford Network. During the project 664 staff received magnesium sulphate training. The use of magnesium sulphate increased across the West of England from an average baseline of 21% over the 2 years preceding the project to 88% by the conclusion of the project. The project was also able to influence the development of a national data collection process for benchmarking the use of magnesium sulphate for neuroprotection in preterm deliveries in the U.K. PReCePT appears to have had a favourable effect on the uptake of magnesium sulphate across the West of England. The project has also provided learning about how to stimulate adoption and spread of evidence using a QI approach across a network.

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.

Combined fetal inflammation and postnatal hypoxia causes myelin deficits and autism-like behavior in a rat model of diffuse white matter injury

Diffuse white matter injury (WMI) is a serious problem in extremely preterm infants, and is associated with adverse neurodevelopmental outcome, including cognitive impairments and an increased risk of autism-spectrum disorders. Important risk factors include fetal or perinatal inflammatory insults and fluctuating cerebral oxygenation. However, the exact mechanisms underlying diffuse WMI are not fully understood and no treatment options are currently available. The use of clinically relevant animal models is crucial to advance knowledge on the pathophysiology of diffuse WMI, allowing the definition of novel therapeutic targets. In the present study, we developed a multiple-hit animal model of diffuse WMI by combining fetal inflammation and postnatal hypoxia in rats. We characterized the effects on white matter development and functional outcome by immunohistochemistry, MRI and behavioral paradigms. Combined fetal inflammation and postnatal hypoxia resulted in delayed cortical myelination, microglia activation and astrogliosis at P18, together with long-term changes in oligodendrocyte maturation as observed in 10 week old animals. Furthermore, rats with WMI showed impaired motor performance, increased anxiety and signs of autism-like behavior, i.e. reduced social play behavior and increased repetitive grooming. In conclusion, the combination of fetal inflammation and postnatal hypoxia in rats induces a pattern of brain injury and functional impairments that closely resembles the clinical situation of diffuse WMI. This animal model provides the opportunity to elucidate pathophysiological mechanisms underlying WMI, and can be used to develop novel treatment options for diffuse WMI in preterm infants.

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.

Antenatal and intrapartum interventions for preventing cerebral palsy: an overview of Cochrane systematic reviews

BACKGROUND

Cerebral palsy is an umbrella term encompassing disorders of movement and posture, attributed to non-progressive disturbances occurring in the developing fetal or infant brain. As there are diverse risk factors and causes, no one strategy will prevent all cerebral palsy. Therefore, there is a need to systematically consider all potentially relevant interventions for their contribution to prevention.

OBJECTIVES

To summarise the evidence from Cochrane reviews regarding the effects of antenatal and intrapartum interventions for preventing cerebral palsy.

METHODS

We searched the Cochrane Database of Systematic Reviews on 7 August 2016, for reviews of antenatal or intrapartum interventions reporting on cerebral palsy. Two authors assessed reviews for inclusion, extracted data, assessed review quality, using AMSTAR and ROBIS, and quality of the evidence, using the GRADE approach. We organised reviews by topic, and summarised findings in text and tables. We categorised interventions as effective (high-quality evidence of effectiveness); possibly effective (moderate-quality evidence of effectiveness); ineffective (high-quality evidence of harm or of lack of effectiveness); probably ineffective (moderate-quality evidence of harm or of lack of effectiveness); and no conclusions possible (low- to very low-quality evidence).

MAIN RESULTS

We included 15 Cochrane reviews. A further 62 reviews pre-specified the outcome cerebral palsy in their methods, but none of the included randomised controlled trials (RCTs) reported this outcome. The included reviews were high quality and at low risk of bias. They included 279 RCTs; data for cerebral palsy were available from 27 (10%) RCTs, involving 32,490 children. They considered interventions for: treating mild to moderate hypertension (two) and pre-eclampsia (two); diagnosing and preventing fetal compromise in labour (one); preventing preterm birth (four); preterm fetal maturation or neuroprotection (five); and managing preterm fetal compromise (one). Quality of evidence ranged from very low to high. Effective interventions: high-quality evidence of effectiveness There was a reduction in cerebral palsy in children born to women at risk of preterm birth who received magnesium sulphate for neuroprotection of the fetus compared with placebo (risk ratio (RR) 0.68, 95% confidence interval (CI) 0.54 to 0.87; five RCTs; 6145 children). Probably ineffective interventions: moderate-quality evidence of harm There was an increase in cerebral palsy in children born to mothers in preterm labour with intact membranes who received any prophylactic antibiotics versus no antibiotics (RR 1.82, 95% CI 0.99 to 3.34; one RCT; 3173 children). There was an increase in cerebral palsy in children, who as preterm babies with suspected fetal compromise, were born immediately compared with those for whom birth was deferred (RR 5.88, 95% CI 1.33 to 26.02; one RCT; 507 children). Probably ineffective interventions: moderate-quality evidence of lack of effectiveness There was no clear difference in the presence of cerebral palsy in children born to women at risk of preterm birth who received repeat doses of corticosteroids compared with a single course (RR 1.03, 95% CI 0.71 to 1.50; four RCTs; 3800 children). No conclusions possible: low- to very low-quality evidence Low-quality evidence found there was a possible reduction in cerebral palsy for children born to women at risk of preterm birth who received antenatal corticosteroids for accelerating fetal lung maturation compared with placebo (RR 0.60, 95% CI 0.34 to 1.03; five RCTs; 904 children). There was no clear difference in the presence of cerebral palsy with interventionist care for severe pre-eclampsia versus expectant care (RR 6.01, 95% CI 0.75 to 48.14; one RCT; 262 children); magnesium sulphate for pre-eclampsia versus placebo (RR 0.34, 95% CI 0.09 to 1.26; one RCT; 2895 children); continuous cardiotocography for fetal assessment during labour versus intermittent auscultation (average RR 1.75, 95% CI 0.84 to 3.63; two RCTs; 13,252 children); prenatal progesterone for prevention of preterm birth versus placebo (RR 0.14, 95% CI 0.01 to 3.48; one RCT; 274 children); and betamimetics for inhibiting preterm labour versus placebo (RR 0.19, 95% CI 0.02 to 1.63; one RCT; 246 children).Very low-quality found no clear difference for the presence of cerebral palsy with any antihypertensive drug (oral beta-blockers) for treatment of mild to moderate hypertension versus placebo (RR 0.33, 95% CI 0.01 to 8.01; one RCT; 110 children); magnesium sulphate for prevention of preterm birth versus other tocolytic agents (RR 0.13, 95% CI 0.01 to 2.51; one RCT; 106 children); and vitamin K and phenobarbital prior to preterm birth for prevention of neonatal periventricular haemorrhage versus placebo (RR 0.77, 95% CI 0.33 to 1.76; one RCT; 299 children).

AUTHORS' CONCLUSIONS

This overview summarises evidence from Cochrane reviews on the effects of antenatal and intrapartum interventions on cerebral palsy, and can be used by researchers, funding bodies, policy makers, clinicians and consumers to aid decision-making and evidence translation. We recommend that readers consult the included Cochrane reviews to formally assess other benefits or harms of included interventions, including impacts on risk factors for cerebral palsy (such as the reduction in intraventricular haemorrhage for preterm babies following exposure to antenatal corticosteroids).Magnesium sulphate for women at risk of preterm birth for fetal neuroprotection can prevent cerebral palsy. Prophylactic antibiotics for women in preterm labour with intact membranes, and immediate rather than deferred birth of preterm babies with suspected fetal compromise, may increase the risk of cerebral palsy. Repeat doses compared with a single course of antenatal corticosteroids for women at risk of preterm birth do not clearly impact the risk of cerebral palsy.Cerebral palsy is rarely diagnosed at birth, has diverse risk factors and causes, and is diagnosed in approximately one in 500 children. To date, only a small proportion of Cochrane reviews assessing antenatal and intrapartum interventions have been able to report on this outcome. There is an urgent need for long-term follow-up of RCTs of interventions addressing risk factors for cerebral palsy, and consideration of the use of relatively new interim assessments (including the General Movements Assessment). Such RCTs must be rigorous in their design, and aim for consistency in cerebral palsy outcome measurement and reporting to facilitate pooling of data, to focus research efforts on prevention.