Chorioamnionitis in the Development of Cerebral Palsy: A Meta-analysis and Systematic Review

Distinguishing Laterality in Brain Injury in Rabbit Fetal Magnetic Resonance Imaging Using Novel Volume Rendering Techniques

INTRODUCTION

Our laboratory has been exploring the MRI detection of fetal brain injury, which previously provided a prognostic biomarker for newborn hypertonia in an animal model of cerebral palsy (CP). The biomarker relies on distinct patterns of diffusion-weighted imaging-defined apparent diffusion coefficient (ADC) in fetal brains during uterine hypoxia-ischemia (H-I). Despite the challenges posed by small brains and tissue acquisition, our objective was to differentiate between left and right brain ADC changes.

METHODS

A novel aspect involved utilizing three-dimensional rendering techniques to refine ADC measurements within spheroids encompassing fetal brain tissue. 25-day gestation age of rabbit fetuses underwent global hypoxia due to maternal uterine ischemia.

RESULTS

Successful differentiation of left and right brain regions was achieved in 28% of the fetal brains. Ordinal analysis revealed predominantly higher ADC on the left side compared to the right at baseline and across the entire time series. During H-I and reperfusion-reoxygenation, the right side exhibited a favored percentage change. Among these fetal brains, 73% exhibited the ADC pattern predictive of hypertonia. No significant differences between left and right sides were observed in patterns predicting hypertonia, except for one timepoint during H-I. This study also highlights a balance between left-sided and right-sided alterations within the population.

CONCLUSION

This study emphasizes the importance of investigating laterality and asymmetric hemispheric lesions for early diagnosis of brain injury, leading to CP. The technological limitations in obtaining a clear picture of the entire fetal brain for every fetus mirror the challenges encountered in human studies.

Intrauterine exposure to chorioamnionitis and neuroanatomical alterations at term-equivalent age in preterm infants

PURPOSE

Infants born to mothers with chorioamnionitis (CAM) are at increased risk of developing adverse neurodevelopmental disorders in later life. However, clinical magnetic resonance imaging (MRI) studies examining brain injuries and neuroanatomical alterations attributed to CAM have yielded inconsistent results. We aimed to determine whether exposure to histological CAM in utero leads to brain injuries and alterations in the neuroanatomy of preterm infants using 3.0- Tesla MRI at term-equivalent age.

METHODS

A total of 58 preterm infants born before 34 weeks of gestation at Nagoya University Hospital between 2010 and 2018 were eligible for this study (CAM group, n = 21; non-CAM group, n = 37). Brain injuries and abnormalities were assessed using the Kidokoro Global Brain Abnormality Scoring system. Gray matter, white matter, and subcortical gray matter (thalamus, caudate nucleus, putamen, pallidum, hippocampus, amygdala, and nucleus accumbens) volumes were evaluated using segmentation tools (SPM12 and Infant FreeSurfer).

RESULTS

The Kidokoro scores for each category and severity in the CAM group were comparable to those observed in the non-CAM group. White matter volume was significantly smaller in the CAM group after adjusting for covariates (postmenstrual age at MRI, infant sex, and gestational age) (p = 0.007), whereas gray matter volume was not significantly different. Multiple linear regression analyses revealed significantly smaller volumes in the bilateral pallidums (right, p = 0.045; left, p = 0.038) and nucleus accumbens (right, p = 0.030; left, p = 0.004) after adjusting for covariates.

CONCLUSIONS

Preterm infants born to mothers with histological CAM showed smaller volumes in white matter, pallidum, and nucleus accumbens at term-equivalent age.

Tocolysis after preterm prelabor rupture of membranes and 5-year outcomes: a population-based cohort study

BACKGROUND

The administration of tocolytics after preterm prelabor rupture of membranes remains a controversial practice. In theory, reducing uterine contractility should delay delivery and allow for optimal antenatal management, thereby reducing the risks for prematurity and adverse consequences over the life course. However, tocolysis may be associated with neonatal death or long-term adverse neurodevelopmental outcomes, mainly related to prolonged fetal exposure to intrauterine infection or inflammation. In a previous study, we showed that tocolysis administration was not associated with short-term benefits. There are currently no data available to evaluate the impact of tocolysis on neurodevelopmental outcomes in school-aged children born prematurely in this clinical setting.

OBJECTIVE

This study aimed to investigate whether tocolysis administered after preterm prelabor rupture of membranes is associated with neurodevelopmental outcomes at 5.5 years of age.

STUDY DESIGN

We used data from a prospective, population-based cohort study of preterm births recruited in 2011 (referred to as the EPIPAGE-2 study) and for whom the results of a comprehensive medical and neurodevelopmental assessment of the infant at age 5.5 years were available. We included pregnant individuals with preterm prelabor rupture of membranes at 24 to 32 weeks' gestation in singleton pregnancies with a live fetus at the time of rupture, birth at 24 to 34 weeks' gestation, and participation of the infant in an assessment at 5.5 years of age. Exposure was the administration of any tocolytic treatment after preterm prelabor rupture of membranes. The main outcome was survival without moderate to severe neurodevelopmental disabilities at 5.5 years of age. Secondary outcomes included survival without any neurodevelopmental disabilities, cerebral palsy, full-scale intelligence quotient, developmental coordination disorders, and behavioral difficulties. A propensity-score analysis was used to minimize the indication bias in the estimation of the treatment effect on outcomes.

RESULTS

Overall, 596 of 803 pregnant individuals (73.4%) received tocolytics after preterm prelabor rupture of membranes. At the 5.5-year follow-up, 82.7% and 82.5% of the children in the tocolysis and no tocolysis groups, respectively, were alive without moderate to severe neurodevelopmental disabilities; 52.7% and 51.1%, respectively, were alive without any neurodevelopmental disabilities. After applying multiple imputations and inverse probability of treatment weighting, we found no association between the exposure to tocolytics and survival without moderate to severe neurodevelopmental disabilities (odds ratio, 0.93; 95% confidence interval, 0.55-1.60), survival without any neurodevelopmental disabilities (odds ratio, 1.02; 95% confidence interval, 0.65-1.61), or any of the other outcomes.

CONCLUSION

There was no difference in the neurodevelopmental outcomes at age 5.5 years among children with and without antenatal exposure to tocolysis after preterm prelabor rupture of membranes. To date, the health benefits of tocolytics remain unproven, both in the short- and long-term.

The aetiology of preterm birth and risks of cerebral palsy and cognitive impairment: A systematic review and meta-analysis

AIM

The associations between the aetiology of preterm birth and later neurodevelopmental outcomes are unclear. A systematic review and meta-analysis examined the existing evidence.

METHODS

The PubMed and Embase databases were searched for papers published in English from inception to 16 December 2020. We included original papers on the causes of preterm birth and the risks of cerebral palsy (CP) and suboptimal cognitive development. Two reviewers independently evaluated the studies and extracted the data.

RESULTS

The literature search yielded 5472 papers and 13 were selected. The aetiology of preterm birth was classified under spontaneous or medically indicated delivery. A meta-analysis was performed, comprising 104 902 preterm infants from 11 papers on CP. Preterm infants born after a medically indicated delivery had a lower CP risk than infants born after spontaneous delivery, with a pooled odds ratio of 0.59 (95% confidence interval 0.40-0.86). This result was robust in the subgroup and sensitivity analyses. Cognitive development was reported in three papers, which suggested that worse outcomes were associated with medically indicated deliveries.

CONCLUSION

The aetiology of preterm delivery may contribute to the risk of CP and cognitive delay. Further research is needed, using individual-level meta-analyses to adjust for possible confounders, notably gestational age.

Clinical Chorioamnionitis and Neurodevelopment at 5 Years of Age in Children Born Preterm: The EPIPAGE-2 Cohort Study

OBJECTIVE

To assess the association between clinical chorioamnionitis and neurodevelopmental disorders at 5 years of age in children born preterm.

STUDY DESIGN

EPIPAGE 2 is a national, population-based cohort study of children born before 35 weeks of gestation in France in 2011. We included infants born alive between 240/7 and 346/7 weeks after preterm labor or preterm premature rupture of membranes. Clinical chorioamnionitis was defined as maternal fever before labor (>37.8°C) with ≥2 of the following criteria: maternal tachycardia, hyperleukocytosis, uterine contractions, purulent amniotic fluid, or fetal tachycardia. The primary outcome was a composite, including cerebral palsy, coordination disorders, cognitive disorders, sensory disorders, or behavioral disorders. We also analyzed each of these disorders separately as secondary outcomes. We performed a multivariable analysis using logistic regression models. We accounted for the nonindependence of twins and missing data by generalized estimating equation models and multiple imputations, respectively.

RESULTS

Among 2927 children alive at 5 years of age, 124 (3%) were born in a context of clinical chorioamnionitis. Overall, 8.2% and 9.6% of children exposed and unexposed, respectively, to clinical chorioamnionitis had moderate-to-severe neurodevelopmental disorders. After multiple imputations and multivariable analysis, clinical chorioamnionitis was not associated with the occurrence of moderate-to-severe neurodevelopmental disorders (aOR, 0.9; 95% CI, 0.5-1.8).

CONCLUSIONS

We did not find any association between clinical chorioamnionitis and neurodevelopmental disorders at 5 years of age in children born at <35 weeks of gestation after preterm labor or preterm premature rupture of membrane.

Key roles of glial cells in the encephalopathy of prematurity

Across the globe, approximately one in 10 babies are born preterm, that is, before 37 weeks of a typical 40 weeks of gestation. Up to 50% of preterm born infants develop brain injury, encephalopathy of prematurity (EoP), that substantially increases their risk for developing lifelong defects in motor skills and domains of learning, memory, emotional regulation, and cognition. We are still severely limited in our abilities to prevent or predict preterm birth. No longer just the "support cells," we now clearly understand that during development glia are key for building a healthy brain. Glial dysfunction is a hallmark of EoP, notably, microgliosis, astrogliosis, and oligodendrocyte injury. Our knowledge of glial biology during development is exponentially expanding but hasn't developed sufficiently for development of effective neuroregenerative therapies. This review summarizes the current state of knowledge for the roles of glia in infants with EoP and its animal models, and a description of known glial-cell interactions in the context of EoP, such as the roles for border-associated macrophages. The field of perinatal medicine is relatively small but has worked passionately to improve our understanding of the etiology of EoP coupled with detailed mechanistic studies of pre-clinical and human cohorts. A primary finding from this review is that expanding our collaborations with computational biologists, working together to understand the complexity of glial subtypes, glial maturation, and the impacts of EoP in the short and long term will be key to the design of therapies that improve outcomes.

Maternal and neonatal outcomes following magnesium sulfate in the setting of chorioamnionitis: a meta-analysis

PURPOSE

Magnesium sulfate (MgSO4) has been widely used in obstetrics as a mean to help decrease maternal and neonatal morbidity in various antenatal pathology. As a factor, it seems to regulate immunity and can, thus, predispose to infectious morbidity. To date, it remains unknown if its administration can increase the risk of chorioamnionitis. In the present meta-analysis, we sought to accumulate the available evidence.

METHODS

We systematically searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL, and Google Scholar databases in our primary search along with the reference lists of electronically retrieved full-text papers.

RESULTS

Eight studies were included that investigated the incidence of chorioamnionitis among parturient that received MgSO4 and control patients. Magnesium sulfate was administered in 3229 women and 3330 women served as controls as they did not receive MgSO4. The meta-analysis of data revealed that there was no association between the administration of magnesium sulfate and the incidence of chorioamnionitis (OR 0.98, 95% CI 0.73, 1.32). Rucker's analysis revealed that small studies did not significantly influence the statistical significance of this finding (OR 1.12, 95% CI 0.82, 1.53). Trial sequential analysis revealed that the required number to safely interpret the primary outcome was not reached. Two studies evaluated the impact of MgSO4 in neonates delivered in the setting of chorioamnionitis. Neither of these indicated the presence of a beneficial effect in neonatal morbidity, including the risk of cerebral palsy, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, sepsis, stillbirth, or neonatal death.

CONCLUSION

Current evidence indicates that magnesium sulfate is not associated with an increased risk of maternal chorioamnionitis. However, it should be noted that its effect on neonatal outcomes of offspring born in the setting of chorioamnionitis might be subtle if any, although the available evidence is very limited.

Prenatal tobacco smoke exposure and risk for cognitive delays in infants born very premature

Prenatal tobacco smoke exposure (TSE) and prematurity are independent risk factors for abnormal neurodevelopment. The objectives were to compare differences in Bayley-III cognitive, language, and motor scores at 2 years corrected age (CA) in 395 infants born very preterm (≤ 32 weeks gestation) with and without prenatal TSE. We performed multivariable linear regression analyses to examine associations between prenatal TSE and neurodevelopmental outcomes and a mediation analysis to estimate direct effects of prenatal TSE on outcomes and indirect effects through preterm birth. In total, 50 (12.6%) infants had prenatal TSE. Infants with prenatal TSE had lower mean [95% CI] Cognitive score (82.8 [78.6, 87.1]) vs. nonexposed infants (91.7 [90.1, 93.4]). In children with and without prenatal TSE, there were significant differences in mean [95% CI] Language scores (81.7 [76.0, 87.4] vs. 92.4 [90.2, 94.6], respectively) and mean [95% CI] Motor scores (86.5 [82.2, 90.7] vs. 93.4 [91.8, 95.0], respectively); scores remained significant after controlling for confounders. Preterm birth indirectly mediated 9.0% of the total effect of prenatal TSE on Cognitive score (P = NS). However, 91% of the remaining total effect was significant and attributable to TSE's direct harmful effects on cognitive development (β = - 5.17 [95% CI - 9.97, - 0.38]). The significant association is largely due to TSE's direct effect on cognitive development and not primarily due to TSE's indirect effect on preterm birth.

Impact of maternal infection on outcomes in extremely preterm infants

BACKGROUND

Infants born less than 29 weeks, or extremely preterm (EPT), experience increased morbidity and mortality. We hypothesized that exposure to maternal infection might contribute to neurodevelopmental impairment (NDI) or death at 2 years of age.

METHODS

We conducted a retrospective cohort study of EPT infants from January 2010 to December 2020. Maternal data extracted included maternal infections, classified as extrauterine or intrauterine. Placental pathologic and infant data were extracted. The primary outcome was NDI or death at 2 years of age.

RESULTS

548 EPT infants were born to 496 pregnant people: 379 (69%) were not exposed to any documented maternal infection prenatally, 124 (23%) to extrauterine infection, and 45 (8%) to intrauterine infection. Neither diagnosis of maternal extrauterine nor intrauterine infection was associated with NDI or death at 2 years of age (p > 0.05). Acute histologic chorioamnionitis was associated with NDI or death at 2 years of age (p = 0.033).

CONCLUSIONS

Maternal infection was not associated with NDI or death at 2 years of age in EPT infants. However, acute histologic chorioamnionitis was associated with this outcome. Further work should investigate the differential influence of infection and immune response with this pathology as relates to outcomes in EPT infants.

IMPACT

Maternal infection was not associated with neurodevelopmental impairment (NDI) or death at 2 years of age in extremely preterm (EPT) infants. This is reassuring support that mechanisms at the maternal-fetal interface largely protect the EPT infant. However, pathologic findings of acute histologic chorioamnionitis were associated with NDI and death at 2 years of age. Further work should investigate the differential influence of infection and immune response with acute histologic chorioamnionitis on pathology as relates to outcomes in EPT infants.

Periventricular hemorrhagic infarction in preterm neonates: Etiology and time of development

BACKGROUND

To find the obstetrical and delivery associated risk factors of antenatal and postnatal grade III intraventricular hemorrhage (IVH) or periventricular hemorrhagic infarction (PVHI) in preterm neonates.

METHODS

A retrospective study of obstetric and delivery associated risk factors included neonates (<35 gestational weeks) with severe IVH/PVHI (n = 120) and a prospectively collected control group (n = 50). The children were divided into: (1) antenatal onset group (n = 27) with insult visible on cerebral ultrasonography within the first 12 hours of birth or periventricular cystic changes visible in PVHI within the first 3 days; (2) neonatal onset group (n = 70) with insult diagnosed after initial normal findings or I-II grade IVH, and (3) unknown time-onset group (n = 23) with insult visible at > 12 h of age.

RESULTS

The mothers of the antenatal onset group had significantly more bacterial infections before delivery compared to the neonatal onset group: 20/27 (74.1%) versus 23/69 (33.3%), (odds ratio (OR) 5.7 [95% confidence interval 2.1-16]; p = 0.0008) or compared to the control group (11/50 (22%); OR 11 [2.8-42]; p = 0.0005). Placental histology revealed chorioamnionitis more often in the antenatal compared to the neonatal onset group (14/21 (66.7%) versus 16/42 (38.1%), respectively; OR 3.7 [1.18-11]; p = 0.025). Neonates with neonatal development of severe IVH/PVHI had significantly more complications during delivery or intensive care.

CONCLUSIONS

Bacterial infection during pregnancy is an important risk factor for development of antenatal onset severe IVH or PVHI. In neonates born to mothers with severe bacterial infection during pregnancy, cerebral ultrasonography is indicated for early detection of severe IVH or PVHI.

Pharmacological blockade of the interleukin-1 receptor suppressed Escherichia coli lipopolysaccharide-induced neuroinflammation in preterm fetal sheep

BACKGROUND

Intraamniotic inflammation is associated with preterm birth, especially in cases occurring before 32 weeks' gestation, and is causally linked with an increased risk for neonatal mortality and morbidity. Targeted anti-inflammatory interventions may assist in improving the outcomes for pregnancies impacted by intrauterine inflammation. Interleukin-1 is a central upstream mediator of inflammation. Accordingly, interleukin-1 is a promising candidate target for intervention therapies and has been targeted previously using the interleukin-1 receptor antagonist, anakinra. Recent studies have shown that the novel, noncompetitive, allosteric interleukin-1 receptor inhibitor, rytvela, partially resolved inflammation associated with preterm birth and fetal injury. In this study, we used a preterm sheep model of chorioamnionitis to investigate the anti-inflammatory efficacy of rytvela and anakinra, administered in the amniotic fluid in the setting of intraamniotic Escherichia coli lipopolysaccharide exposure.

OBJECTIVE

We hypothesized that both rytvela and anakinra would reduce lipopolysaccharide-induced intrauterine inflammation and protect the fetal brain.

STUDY DESIGN

Ewes with a singleton fetus at 105 days of gestation (term is ∼150 days) were randomized to one of the following groups: (1) intraamniotic injections of 2 mL saline at time=0 and time=24 hours as a negative control group (saline group, n=12); (2) intraamniotic injection of 10 mg Escherichia coli lipopolysaccharide in 2 mL saline and intraamniotic injections of 2 mL saline at time=0 hours and time=24 hours as an inflammation positive control group (lipopolysaccharide group, n=11); (3) intraamniotic injection of Escherichia coli lipopolysaccharide in 2 mL saline and intraamniotic injections of 2.5 mg rytvela at time=0 hours and time=24 hours to test the anti-inflammatory efficacy of rytvela (lipopolysaccharide + rytvela group, n=10); or (4) intraamniotic injection of Escherichia coli lipopolysaccharide in 2 mL saline and intraamniotic injections of 100 mg anakinra at time=0 hours and time=24 hours to test the anti-inflammatory efficacy of anakinra (lipopolysaccharide + anakinra group, n=12). Amniotic fluid was sampled at time 0, 24, and 48 hours (ie, at each intervention and at delivery). Fetal umbilical cord blood was collected at delivery for differential blood counts and chemical studies. Inflammation was characterized by the analysis of fetal tissue cytokine and chemokine levels using quantitative polymerase chain reaction, enzyme-linked inmmunosorbent assay, and histology. The primary study outcome of interest was the assessment of anakinra and rytvela brain-protective effects in the setting of Escherichia coli lipopolysaccharide-induced intrauterine inflammation. Secondary outcomes of interest were to assess protection from fetal and intrauterine (ie, amniotic fluid, chorioamnion) inflammation.

RESULTS

Intraamniotic administration of lipopolysaccharide caused inflammation of the fetal lung, brain, and chorioamnionitis in preterm fetal sheep. Relative to treatment with saline only in the setting of lipopolysaccharide exposure, intraamniotic administration of both rytvela and anakinra both significantly prevented periventricular white matter injury, microglial activation, and histologic chorioamnionitis. Anakinra showed additional efficacy in inhibiting fetal lung myeloperoxidase activity, but its use was associated with metabolic acidaemia and reduced fetal plasma insulin-like growth factor-1 levels at delivery.

CONCLUSION

Intraamniotic administration of rytvela or anakinra significantly inhibited fetal brain inflammation and chorioamnionitis in preterm fetal sheep exposed to intraamniotic lipopolysaccharide. In addition, anakinra treatment was associated with potential negative impacts on the developing fetus.

Establishment of a prediction model for histological chorioamnionitis and its association with outcomes of premature infants

Aim

This study aims to construct a prediction model for histological chorioamnionitis (HCA) and analyze the associations between the predicted risk of HCA and adverse outcomes in preterm infants.

Methods

In total, 673 subjects were included in this cohort study and divided into HCA group (n = 195) and non-HCA group (n = 478). A stepwise method was used to screen the predictors for HCA, binary logistic regression was used to construct the prediction model, and the associations between the predicted risk of HCA and adverse outcomes were analyzed.

Results

HCA occurred in 195 patients, accounting for 29.0%. The sensitivity of the prediction model was 0.821 [95% confidence interval (CI): 0.767-0.874)], the specificity was 0.684 (95% CI: 0.642-0.726), the positive predictive value was 0.514 (0.459-0.570), the negative predictive value was 0.903 (95% CI: 0.873-0.934), the area under the curve was 0.821 (95% CI: 0.786-0.855), and the accuracy was 0.724 (95% CI: 0.690-0.757). The predicted risk of HCA was associated with a higher risk of bronchopulmonary dysplasia (BPD) [odds ratio (OR) = 3.48, 95% CI: 1.10-10.95)], sepsis (OR = 6.66, 95% CI: 2.17-20.43), and neonatal infections (OR = 9.85, 95% CI: 3.59-26.98), but not necrotizing enterocolitis (OR = 0.67, 95% CI: 0.24-1.88), retinopathy of prematurity (OR = 1.59, 95% CI: 0.37-6.85), and brain damage (OR = 1.77, 95% CI: 0.82-3.83). After adjusting for confounders including gestational week at birth and birth weight, the risk of neonatal infections (OR = 5.03, 95% CI: 2.69-9.41) was increased in preterm infants' exposure to HCA.

Conclusion

The model showed good predictive performance for identifying pregnant women with a higher risk of HCA. In addition, HCA was associated with the risk of BPD, sepsis, and infections in neonates.

Perinatal inflammation exposure and developmental outcomes 7 years after neonatal arterial ischaemic stroke

AIM

To test the association between perinatal inflammation exposure and Full-Scale IQ (FSIQ) score 7 years after neonatal arterial ischaemic stroke (NAIS).

METHOD

We conducted a cross-sectional ancillary study nested in a multicentric longitudinal French cohort of infants born at term with NAIS between November 2003 and October 2006. Seventy-three children were included (45 males, 28 females). The a priori defined primary outcome measure was the FSIQ score assessed with the Wechsler Intelligence Scale for Children, Fourth Edition at 7 years of age.

RESULTS

Seventeen (23%) of the included children were exposed to perinatal inflammation. Exposure to perinatal inflammation was independently associated with an increase of FSIQ score (coefficient 13.4, 95% confidence interval 1.3-25.4; p = 0.03). Children exposed to perinatal inflammation had a higher median cerebral volume, a lower median lesion volume, and less extensive lesion distributions compared to non-exposed children.

INTERPRETATION

We propose the existence of two NAIS categories: arteritis-associated NAIS in children exposed to perinatal inflammation and embolism-associated NAIS in children non-exposed to perinatal inflammation. Identifying these two NAIS categories would open the possibility for specific curative strategies: anti-inflammatory strategy in arteritis-associated NAIS and recanalization strategy in embolism-associated NAIS.

Relationship of maternal inflammatory response and fetal inflammatory response to duration and intensity of intra-amniotic infection and inflammation

INTRODUCTION

We aimed to use two indices, amniotic fluid interleukin-6 (IL-6) concentration at diagnosis and diagnosis-to-delivery interval, to clarify the frequencies of maternal inflammatory response (MIR) and fetal inflammatory response (FIR) in the placenta of patients with intra-amniotic infection and intra-amniotic inflammation (IAI).

METHODS

This is a single-center retrospective cohort study. From August 2014 to April 2020, participants were diagnosed with IAI with or without microbial invasion of the amniotic cavity (MIAC) using amniocentesis. IAI was defined as concentrations of amniotic IL-6 ≥ 2.6 ng/mL. MIAC was defined as a positive amniotic fluid culture. IAI with MIAC was defined as an intra-amniotic infection. We calculated the cut-off values for IL-6 concentration in the amniotic fluid at diagnosis and the diagnosis-to-delivery interval for MIR-positive cases among those with intra-amniotic infection.

RESULTS

The amniotic fluid IL-6 concentration at diagnosis and diagnosis-to-delivery interval were 15.8 ng/mL and 12 h, respectively. Among cases with intra-amniotic infection, MIR was 98% (52/53) positive, i.e., when either of the two cut-off values was exceeded. There were no significant differences between the frequencies of MIR and FIR. In cases with IAI but no MIAC, the frequencies of MIR and FIR were significantly lower than those with intra-amniotic infection, except when neither of the two cut-off values was exceeded.

DISCUSSION

We clarified the MIR- and FIR-positive cases in intra-amniotic infection and cases with IAI but no MIAC according to condition, including the diagnosis-to-delivery interval.

Booster course of antenatal corticosteroids after preterm prelabor rupture of membranes: a double-blind randomized trial

BACKGROUND

Preterm prelabor rupture of membranes is a leading cause of preterm birth and is responsible for 18% to 20% of perinatal deaths in the United States. An initial course of antenatal corticosteroids has been shown to reduce morbidity and mortality in patients with preterm prelabor rupture of membranes. For patients who remain undelivered for 7 days or more after the initial course of antenatal corticosteroids, it is uncertain whether a booster course of antenatal corticosteroids reduces neonatal morbidity or increases the infection risk. The American College of Obstetricians and Gynecologists has concluded that the current evidence is insufficient to make a recommendation.

OBJECTIVE

This study aimed to evaluate if a single booster course of antenatal corticosteroids improves neonatal outcomes after preterm prelabor rupture of membranes.

STUDY DESIGN

We conducted a multicenter, placebo-controlled randomized clinical trial. The inclusion criteria were preterm prelabor rupture of membranes, gestational age of 24.0 to 32.9 weeks, singleton, initial antenatal corticosteroid course administered at least 7 days before randomization, and planned expectant management. Consenting patients were randomized in gestational age blocks to either receive booster antenatal corticosteroids (12 mg betamethasone every 24 hours for 2 days) or a saline placebo. The primary outcome was composite neonatal morbidity or death. A sample size of 194 patients was calculated to yield 80% power at P<.05 to detect a reduction in primary outcome from 60% in placebo group to 40% in antenatal corticosteroids group.

RESULTS

From April 2016 through August 2022, 194 patients consented and were randomized (47% of 411 eligible patients). Intent-to-treat analysis was performed on 192 patients (2 placebo patients left hospital, outcomes unknown). The groups had similar baseline characteristics. The primary outcome occurred in 64% of patients who received booster antenatal corticosteroids vs in 66% of patients who received the placebo (odds ratio, 0.82; 95% confidence interval, 0.43-1.57; gestational age-stratified Cochran-Mantel-Haenszel test). Individual components of the primary outcome and secondary neonatal and maternal outcomes were not significantly different between the antenatal corticosteroids and placebo groups. Specifically, chorioamnionitis (22% vs 20%), postpartum endometritis (1% vs 2%), wound infections (2% vs 0%), and proven neonatal sepsis (5% vs 3%) were not different between the groups.

CONCLUSION

A booster course of antenatal corticosteroids at least 7 days after the first antenatal corticosteroids course in patients with preterm prelabor rupture of membranes did not improve neonatal morbidity or any other outcome in this adequately-powered, double-blind randomized clinical trial. Booster antenatal corticosteroids did not increase maternal or neonatal infection.

The Role of the Interleukin-1 Family in Complications of Prematurity

Preterm birth is a major contributor to neonatal morbidity and mortality. Complications of prematurity such as bronchopulmonary dysplasia (BPD, affecting the lung), pulmonary hypertension associated with BPD (BPD-PH, heart), white matter injury (WMI, brain), retinopathy of prematurity (ROP, eyes), necrotizing enterocolitis (NEC, gut) and sepsis are among the major causes of long-term morbidity in infants born prematurely. Though the origins are multifactorial, inflammation and in particular the imbalance of pro- and anti-inflammatory mediators is now recognized as a key driver of the pathophysiology underlying these illnesses. Here, we review the involvement of the interleukin (IL)-1 family in perinatal inflammation and its clinical implications, with a focus on the potential of these cytokines as therapeutic targets for the development of safe and effective treatments for early life inflammatory diseases.

Placental Changes and Neuropsychological Development in Children-A Systematic Review

Placental dysfunction may increase the offspring's later-life disease risk. The objective of this systematic review was to describe associations between pathological placental changes and neuropsychological outcomes in children after the neonatal period. The inclusion criteria were human studies; original research; direct placental variables; neuropsychological outcomes; and analysis between their associations. The exclusion criterion was the offspring's age-0-28 days or >19 years. The MEDLINE and EMBASE databases were last searched in May 2022. We utilized the ROBINS-I for the risk of bias assessment and performed a narrative synthesis. In total, 3252 studies were identified, out of which 16 were included (i.e., a total of 15,862 participants). Half of the studies were performed on children with neonatal complications, and 75% of the studies reported an association between a placental change and an outcome; however, following the completion of the funnel plots, a risk of publication bias was indicated. The largest study described a small association between placental size and a risk of psychiatric symptoms in boys only. Inconsistency between the studies limited the evidence in this review. In general, no strong evidence was found for an association between pathological placental changes and childhood neuropsychological outcomes after the neonatal period. However, the association between placental size and mental health in boys indicates a placental sexual dimorphism, thereby suggesting an increased vulnerability for male fetuses.

Criteria for placental examination for obstetrical and neonatal providers

Pathologic examination of the placenta can provide insight into likely (and unlikely) causes of antepartum and intrapartum events, diagnoses with urgent clinical relevance, prognostic information for mother and infant, support for practice evaluation and improvement, and insight into advancing the sciences of obstetrics and neonatology. Although it is true that not all placentas require pathologic examination (although alternative opinions have been expressed), prioritization of placentas for pathologic examination should be based on vetted indications such as maternal comorbidities or pregnancy complications in which placental pathology is thought to be useful for maternal or infant care, understanding pathophysiology, or practice modifications. Herein we provide placental triage criteria for the obstetrical and neonatal provider based on publications and expert opinion of 16 placental pathologists and a pathologists' assistant, formulated using a modified Delphi approach. These criteria include indications in which placental pathology has clinical relevance, such as pregnancy loss, maternal infection, suspected abruption, fetal growth restriction, preterm birth, nonreassuring fetal heart testing requiring urgent delivery, preeclampsia with severe features, or neonates with early evidence of multiorgan system failure including neurologic compromise. We encourage a focused gross examination by the provider or an attendant at delivery for all placentas and provide guidance for this examination. We recommend that any placenta that is abnormal on gross examination undergo a complete pathology examination. In addition, we suggest practice criteria for placental pathology services, including a list of critical values to be used by the relevant provider. We hope that these sets of triage indications, criteria, and practice suggestions will facilitate appropriate submission of placentas for pathologic examination and improve its relevance to clinical care.

Placental pathology as a marker of brain injury in infants with hypoxic ischemic encephalopathy

BACKGROUND

Hypoxic Ischemic Encephalopathy (HIE) can lead to devastating consequences for the affected infant. Although therapeutic cooling benefits infants with moderate and severe HIE, differentiating mild from moderate-severe HIE may be challenging. The placenta reflects the fetal intrauterine environment and may reveal underlying processes that affect brain injury.

AIM

To describe placental histopathology using the Amsterdam Placental Workshop Group Criteria in different grades of HIE.

STUDY DESIGN

Retrospective cohort.

SUBJECTS

Infants admitted to a tertiary care neonatal intensive care unit with a diagnosis of HIE between 2011 and 2016.

OUTCOME MEASURE

Maternal and neonatal clinical variables and placental histopathology using the Amsterdam Placental Workshop Group Criteria were compared between mild and moderate-severe HIE. Mann-Whitney or t-test or ꭓ² were performed for bivariate associations as appropriate. To explain the relationship between placental pathology and severity of HIE odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using logistic regression models.

RESULTS

Of the 73 infants in the study, 23 had mild and 50 moderate-sever HIE. There was no difference in maternal and neonatal characteristics except for sentinel events which were higher in the moderate- severe group. On placental histopathology, acute inflammation, including fetal inflammatory reaction (FIR) were significantly higher in the moderate-severe group. After adjusting for confounders, FIR remained significantly associated with moderate-severe HIE, ORs 6.29, 95 % CI 1.5-25.

CONCLUSION

Our study demonstrates FIR in the placenta is associated with severity of HIE.

Acute histologic chorioamnionitis independently and directly increases the risk for brain abnormalities seen on magnetic resonance imaging in very preterm infants

BACKGROUND

The independent risk for neurodevelopmental impairments attributed to chorioamnionitis in premature infants remains controversial. Delayed brain maturation or injury identified on magnetic resonance imaging at term-equivalent age can be used as a surrogate measure of neurodevelopmental impairments that is less confounded by postdelivery neonatal intensive care unit environmental factors to investigate this relationship more clearly.

OBJECTIVE

This study aimed to determine whether preterm infants born with moderate to severe acute histologic chorioamnionitis would have a higher magnetic resonance imaging-determined global brain abnormality score, independent of early premature birth, when compared with preterm infants with no or mild chorioamnionitis.

STUDY DESIGN

This was a prospective, multicenter cohort study involving infants born very prematurely ≤32 weeks' gestational age with acute moderate to severe histologic chorioamnionitis, graded using standard histologic criteria. Brain abnormalities were diagnosed and scored using a well-characterized, standardized scoring system captured using a high-resolution 3 Tesla magnetic resonance imaging research magnet. In secondary analyses, total brain volume and 4 magnetic resonance imaging metrics of cortical maturation (cortical surface area, sulcal depth, gyral index, and inner cortical curvature) were calculated using an automated algorithm and correlated with chorioamnionitis. The association of funisitis (any grade) with brain abnormalities was also explored. We investigated if premature birth mediated the relationship between histologic chorioamnionitis and brain abnormality score using mediation analysis.

RESULTS

Of 353 very preterm infants, 297 infants had mild or no chorioamnionitis (controls), and 56 were diagnosed with moderate to severe acute histologic chorioamnionitis. The primary outcome brain abnormality score was significantly higher in histologic chorioamnionitis-exposed infants than in the controls (median, 4 vs 7; P<.001). Infants with acute histologic chorioamnionitis had significantly lower brain tissue volume (P=.03) and sulcal depth (P=.04), whereas other morphometric indices did not differ statistically. In the multiple regression analysis, we observed persistent significant relationships between moderate to severe acute histologic chorioamnionitis and brain abnormality scores (β=2.84; 1.51-4.16; P<.001), total brain volume (P=.03), and sulcal depth (P=.02). Funisitis was also significantly associated with brain abnormality score after adjustment for clinical confounders (P=.005). Mediation analyses demonstrated that 50% of brain abnormalities was an indirect consequence of premature birth, and the remaining 50% was a direct effect of moderate to severe acute histologic chorioamnionitis when compared with preterm infants with no or mild chorioamnionitis exposure. Examining gestational age as a mediator, funisitis did not exert a significant direct effect on brain abnormalities after the significant indirect effects of preterm birth were accounted for.

CONCLUSION

Acute histologic chorioamnionitis increases the risk for brain injury and delayed maturation, both directly and indirectly, by inducing premature birth.

Is chorioamnionitis associated with hearing impairment in preterm infants? A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

It has been reported that chorioamnionitis (CA) could increase the risk of hearing impairment in premature infants, but results are inconsistent. A meta-analysis was performed to systematically evaluate the relationship between CA and hearing impairment in premature infants.

MATERIAL AND METHODS

Search in PubMed, Embase, Cochrane Library from their inception to May 2020. We concluded all cohort and case-control studies which explored the associations between CA and hearing impairment in preterm infants. Pregnant women with other infections besides CA were excluded. PRISMA guidelines were followed. Fixed-and random-effects models were used, depending on heterogeneity. And we performed to calculate odds ratio (ORs), and 95% CIs using fixed-effects models.

RESULTS

Seven studies involving 4134 premature infants were included. There was non-significant association between CA and hearing impairment (adjusted OR 1.43, 95% CI 0.99 to 2.04, P = 0.05; heterogeneity: I² = 13%, P = 0.33).

CONCLUSION

This article concludes that CA is not a risk factor for hearing impairment in premature infants, but most of the current studies are retrospective studies with low intensity and lack of high-quality articles to discuss it.

Protecting the brain of the micropreemie

Advances in perinatal care have seen substantial improvements in survival without disability for extremely preterm infants. Protecting the developing brain and reducing neurodevelopmental sequelae of extremely preterm birth are strategic priorities for both research and clinical care. A number of evidence-based interventions exist for neuroprotection in micropreemies, inclusive of prevention of preterm birth and multiple births with implantation of only one embryo during in vitro fertilisation, as well as antenatal care to optimize fetal wellbeing, strategies for supporting neonatal transition, and neuroprotective developmental care. Avoidance of complications that trigger ischemia and inflammation is vital for minimizing brain dysmaturation and injury, particularly of the white matter. Neurodevelopmental surveillance, early diagnosis of cerebral palsy and early intervention are essential for optimizing long-term outcomes and quality of life. Research priorities include further evaluation of putative neuroprotective agents, and investigation of common neonatal interventions in trials adequately powered to assess neurodevelopmental outcome.

Histological severity of maternal and fetal inflammation is correlated with the prevalence of maternal clinical signs

AIM

To evaluate whether there is a stepwise increase in the prevalence of maternal clinical signs according to the severity of histological inflammation in the chorioamniotic membranes, placenta, and umbilical cord in preterm deliveries.

METHODS

This retrospective study, conducted between January 2007 and May 2017, included patients with preterm delivery between 22 and 33 weeks. The histological findings of maternal/fetal inflammatory responses were staged and graded according to the Amsterdam Placental Workshop Group consensus statement. Correlations between the histological severity of maternal/fetal inflammatory responses and the prevalence of clinical chorioamnionitis and clinical signs were evaluated using the Cochran-Armitage trend test.

RESULTS

A total of 138 patients were included. The stage and grade of the maternal inflammatory response were correlated with earlier gestational weeks at delivery and lighter birth weight. The prevalence of clinical chorioamnionitis was significantly correlated with a higher stage and grade of the maternal inflammatory response (Gibbs/Lencki criteria: 15.8%/15.8% in Stage 3, 16.3%/14% in Grade 2). No significant correlations were observed between gestational weeks at delivery and birth weight and stage/grade of fetal inflammatory response. The prevalence of clinical chorioamnionitis was significantly correlated with higher stage and grade of fetal inflammatory response (Gibbs/Lencki criteria: 25%/25% in Stage 3 and 29.4%/29.4% in Grade 2).

CONCLUSION

Correlations exist between the severity of histological maternal/fetal inflammatory responses and the prevalence of clinical chorioamnionitis and positive maternal clinical signs in preterm deliveries. However, the prevalence of clinical chorioamnionitis was 20%-30% even in the most severe fetal inflammatory responses.

Adverse Prenatal Exposures and Fetal Brain Development: Insights From Advanced Fetal Magnetic Resonance Imaging

Converging evidence from clinical and preclinical studies suggests that fetal vulnerability to adverse prenatal exposures increases the risk for neuropsychiatric diseases such as autism spectrum disorder, schizophrenia, and depression. Recent advances in fetal magnetic resonance imaging have allowed us to characterize typical fetal brain growth trajectories in vivo and to interrogate structural and functional alterations associated with intrauterine exposures, such as maternal stress, environmental toxins, drugs, and obesity. Here, we review proposed mechanisms for how prenatal influences disrupt neurodevelopment, including the role played by maternal and fetal inflammatory responses. We summarize insights from magnetic resonance imaging research in fetuses, highlight recent discoveries in normative fetal development using quantitative magnetic resonance imaging techniques (i.e., three-dimensional volumetry, proton magnetic resonance spectroscopy, placental diffusion imaging, and functional imaging), and discuss how baseline trajectories are shaped by prenatal exposures.

Chorioamnionitis and neonatal outcomes

Chorioamnionitis or intrauterine inflammation is a frequent cause of preterm birth. Chorioamnionitis can affect almost every organ of the developing fetus. Multiple microbes have been implicated to cause chorioamnionitis, but "sterile" inflammation appears to be more common. Eradication of microorganisms has not been shown to prevent the morbidity and mortality associated with chorioamnionitis as inflammatory mediators account for continued fetal and maternal injury. Mounting evidence now supports the concept that the ensuing neonatal immune dysfunction reflects the effects of inflammation on immune programming during critical developmental windows, leading to chronic inflammatory disorders as well as vulnerability to infection after birth. A better understanding of microbiome alterations and inflammatory dysregulation may help develop better treatment strategies for infants born to mothers with chorioamnionitis.

Placental mediated mechanisms of perinatal brain injury: Evolving inflammation and exosomes

Pregnancy is an inflammatory process that is carefully regulated by the placenta via immunomodulation and cell-to-cell communication of maternal and fetal tissues. Exosomes, types of extracellular vesicles, facilitate the intercellular communication and traffic biologically modifying cargo within the maternal-placental-fetal axis in normal and pathologic pregnancies. Chorioamnionitis is characterized by inflammation of chorioamniotic membranes that produces systemic maternal and fetal inflammatory responses of cytokine dysregulation and has been associated with brain injury and neurodevelopmental disorders. This review focuses on how pathologic placental exosomes propagate acute and chronic inflammation leading to brain injury. The evidence reviewed here highlights the need to investigate exosomes from pathologic pregnancies and those with known brain injury to identify new diagnostics, biomarkers, and potential therapeutic targets.

The impact of perinatal inflammation on the electroencephalogram in preterm infants: a systematic review

BACKGROUND

To summarise the association between perinatal inflammation (PI) exposure and electroencephalography (EEG) features in preterm infants.

METHODS

This systematic review included clinical studies of preterm infants born <37 weeks of gestational age (GA), who had both a PI exposure and an EEG assessment performed during the neonatal period. Studies were identified from Medline and Embase databases on the 15th of September 2021. PI was defined by histological chorioamnionitis, clinical chorioamnionitis, or early-onset neonatal infection (EONI). The risk of bias in included studies was assessed using the Joanna Briggs Institute (JBI) appraisal tool. A narrative approach was used to synthesise results. This review followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement.

RESULTS

Two cross-sectional studies enrolling 130 preterm children born <32 weeks of GA assessed with one-channel amplitude-integrated EEG (aEEG) during the first four days of life were included. A PI exposure was described in 39 (30%) infants and was associated with a decrease in amplitude and a reduced incidence of sleep-wake cycling patterns.

CONCLUSION

These results should be interpreted with caution because of the small number of included studies and their heterogeneity. Further clinical studies evaluating the association of PI with EEG findings are needed.

IMPACT

A method to assess developmental trajectories following perinatal inflammation is required. Insufficient data exist to determine EEG features associated with perinatal inflammation. Further clinical studies evaluating this association are needed.

Developmental Stressors Induce Innate Immune Memory in Microglia and Contribute to Disease Risk

Many types of stressors have an impact on brain development, function, and disease susceptibility including immune stressors, psychosocial stressors, and exposure to drugs of abuse. We propose that these diverse developmental stressors may utilize a common mechanism that underlies impaired cognitive function and neurodevelopmental disorders such as schizophrenia, autism, and mood disorders that can develop in later life as a result of developmental stressors. While these stressors are directed at critical developmental windows, their impacts are long-lasting. Immune activation is a shared pathophysiology across several different developmental stressors and may thus be a targetable treatment to mitigate the later behavioral deficits. In this review, we explore different types of prenatal and perinatal stressors and their contribution to disease risk and underlying molecular mechanisms. We highlight the impact of developmental stressors on microglia biology because of their early infiltration into the brain, their critical role in brain development and function, and their long-lived status in the brain throughout life. Furthermore, we introduce innate immune memory as a potential underlying mechanism for developmental stressors' impact on disease. Finally, we highlight the molecular and epigenetic reprogramming that is known to underlie innate immune memory and explain how similar molecular mechanisms may be at work for cells to retain a long-term perturbation after exposure to developmental stressors.

Preterm Birth Is Associated With Immune Dysregulation Which Persists in Infants Exposed to Histologic Chorioamnionitis

Introduction

Preterm infants are at increased risk of exposure to histologic chorioamnionitis (HCA) when compared to term-born controls, and this is associated with several neonatal morbidities involving brain, lungs and gut. Preterm infants could benefit from immunomodulatory therapies in the perinatal period, but development of rational treatment strategies requires improved characterization of the perinatal response to HCA. We had two objectives: The first, to characterize the umbilical cord blood immune profile in preterm infants compared to term-born controls; the second, to investigate the postnatal immune response in preterm infants exposed to HCA versus those who were not.

Population

For objective one 59 term infants [mean gestational age (GA) 39⁺⁴ (37⁺³ to 42⁺⁰)] and 55 preterm infants [mean GA29⁺⁰(23⁺³ to 32⁺⁰)] with umbilical cord samples available were included; for objective two we studied 96 preterm infants [mean GA29⁺¹(23⁺² to 32⁺⁰)] for whom placental histology and postnatal blood samples were available.

Methods

Placental histopathology was used to identify reaction patterns indicative of HCA, and a customized immunoassay of 24 inflammatory markers and trophic proteins selected to reflect the perinatal immune response was performed on umbilical cord blood in term and preterm participants and postnatal day 5 blood in the preterm group.

Results

The umbilical cord blood immune profile classified gestational age category with 86% accuracy (95% CI 0.78-0.92), p-value=1.242x10^-14. Pro-inflammatory proteins IL-6, MCP-1 and CRP were elevated in the cord blood of preterm infants whilst BDNF, C3, C9, IL-18, MMP-9 and RANTES were decreased, compared to infants born at term. In preterm infants, exposure to HCA was associated with elevations in 8 immune proteins on postnatal day 5 (BDNF, C3, C5a, C9, IL-8, MCP-1, MIP-1β and MMP-9) when compared to preterm infants who were not exposed.

Conclusion

Preterm birth is associated with a distinct immune profile in umbilical cord blood and preterm infants exposed to HCA with evidence of a fetal inflammatory response have specific alterations in immune function that are apparent on day 5 of postnatal life.

Intrapartum and Postpartum Management of Intra-amniotic Infection

Importance

Intra-amniotic infection (IAI) is a common condition with potentially devastating maternal and neonatal complications. However, there are incomplete data regarding the most effective antimicrobial treatment regimen for this condition.

Objective

This article aims to review the current evidence and recommendations for intrapartum and postpartum management of IAI.

Evidence Acquisition

Original research articles, review articles, and guidelines on IAI were reviewed.

Results

Numerous known risk factors for IAI exist, some of which are modifiable. Serious neonatal complications can result from exposure to IAI including increased risk of preterm birth and neonatal death. Possible maternal complications include increased risk of cesarean delivery, postpartum hemorrhage, and postpartum endometritis. Antibiotics are the mainstay of treatment for IAI for both mothers and neonates, although there is no consensus on which antimicrobial agents are best and the appropriate duration of therapy.

Conclusions and Relevance

Monitoring patients for signs of IAI, proper treatment, and communication of the diagnosis with the pediatric team are essential for preventing maternal and neonatal complications of IAI. More research is needed to determine the proper treatment regimens for both mothers diagnosed with IAI and their neonates.

Association of Infection in Neonates and Long-Term Neurodevelopmental Outcome

Perinatal and neonatal infection and associated inflammatory response may adversely affect brain development and lead to neurodevelopmental impairment. Factors that predict the risk of infection and subsequent adverse outcomes have been identified but substantial gaps remain in identifying mechanisms and interventions that can alter outcomes. This article describes the current epidemiology of neonatal sepsis, the pathogenesis of brain injury with sepsis, and the reported long-term neurodevelopment outcomes among survivors.

Maternal Infection During Pregnancy and Risk of Cerebral Palsy in Children: A Systematic Review and Meta-analysis

BACKGROUND AND AIM

The association between maternal infection during pregnancy and the risk of cerebral palsy has been previously reported. However, their results were relatively inconsistent. This systematic review and meta-analysis were carried out to investigate the association between maternal infection during pregnancy and the risk of cerebral palsy in children.

METHODS

PubMed, Scopus, and Web of Sciences databases were searched from inception to October 28, 2019. Heterogeneity was assessed using the I² value. In case of substantial heterogeneity (I² > 50%), a random effects model was applied, otherwise, a fixed effects model was used. The pooled associations were expressed as relative risks (RRs) and 95% confidence intervals (CIs). Publication bias and quality of studies included in the systematic review were checked using the Egger's regression test and Newcastle-Ottawa Scale (NOS), respectively.

RESULTS

Thirty-seven studies were included in the systematic review. Among them, 21 studies were eligible for the meta-analysis. The pooled RR of cerebral palsy risk was 2.50 (95% CI 1.94, 3.21; I² = 88.7%, P < .001) among children born to mothers who had any infection during pregnancy. The risk was increased to 2.85 (95% CI 1.96, 4.15; I² = 75.9%, P < .001) when the mother was diagnosed with chorioamnionitis. Publication bias tests suggested no evidence of potential publication bias and 76% of the studies included in the meta-analysis were of high quality (NOS ≥ 6).

CONCLUSION

This systematic review and meta-analysis provides evidence that maternal infection during pregnancy may be associated with an increased risk of cerebral palsy in children.

Biomarkers for a histological chorioamnionitis diagnosis in pregnant women with or without group B streptococcus infection: a case-control study

Background

Chorioamnionitis may cause serious perinatal and neonatal adverse outcomes, and group B streptococcus (GBS) is one of the most common bacteria isolated from human chorioamnionitis. The present study analyzed the impact of GBS infection and histological chorioamnionitis (HCA) on pregnancy outcomes and the diagnostic value of various biomarkers.

Methods

Pregnant women were grouped according to GBS infection and HCA detection. Perinatal and neonatal adverse outcomes were recorded with a follow-up period of 6 weeks. The white blood cell count (WBC), neutrophil ratio, and C-reactive protein (CRP) level from peripheral blood and soluble intercellular adhesion molecule-1 (sICAM-1), interleukin 8 (IL-8), and tumor necrosis factor α (TNF-α) levels from cord blood were assessed.

Results

A total of 371 pregnant women were included. Pregnant women with GBS infection or HCA had a higher risk of pathological jaundice and premature rupture of membranes and higher levels of sICAM-1, IL-8, and TNF-α in umbilical cord blood. Univariate and multivariate regression analysis revealed that sICMA-1, IL-8, TNF-α, WBC, and CRP were significantly related to an increased HCA risk. For all included pregnant women, TNF-α had the largest receiver operating characteristic (ROC) area (area: 0.841; 95% CI: 0.778–0.904) of the biomarkers analyzed. TNF-α still had the largest area under the ROC curve (area: 0.898; 95% CI: 0.814–0.982) for non-GBS-infected pregnant women, who also exhibited a higher neutrophil ratio (area: 0.815; 95% CI: 0.645–0.985) and WBC (area: 0.849; 95% CI: 0.72–0.978), but all biomarkers had lower value in the diagnosis of HCA in GBS-infected pregnant women.

Conclusion

GBS infection and HCA correlated with several perinatal and neonatal adverse outcomes. TNF-α in cord blood and WBCs in peripheral blood had diagnostic value for HCA in non-GBS-infected pregnant women but not GBS-infected pregnant women.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03731-7.

Chorioamnionitis in utero, schizophrenia in adulthood: limited current evidence-future research focus?

Background: Developmental adaptive processes during gestation that are known to be involved in permanent changes in physiology and metabolism or "early life programming" can adversely affect fetal brain development, impacting both brain structure and function.Data: Emerging evidence strongly supports the developmental origin of schizophrenia, which may potentially be a result of prenatal exposure to a diversity of factors, especially infections, in genetically predisposed subjects. Structural and functional brain changes during development of schizophrenia are determined by genetic components, altered expression of schizophrenia risk genes and epigenetic dysregulation. However, the precise mechanisms underlying these relationships remain unclear. Findings from human and animal studies suggest that inflammatory-immune responses and activation of oxidative stress pathways are crucial in mediating intrauterine infection-induced neurodevelopmental and neuropsychiatric diseases.Aim: Considering the high prevalence of intrauterine inflammation in the context of chorioamnionitis during human pregnancy and the paucity of knowledge on fetal programming of schizophrenia, this mini review aims to exclusively consolidate the current evidence supporting a potential association between chorioamnionitis and schizophrenia.

Cord Blood Cytokine Levels Correlate With Types of Placental Pathology in Extremely Preterm Infants

Background: Placental abnormalities are associated with inflammation and have been linked to brain injury in preterm infants. We studied the relationship between placental pathology and the temporal profiles of cytokine levels in extremely pre-term infants. Study Design: We prospectively enrolled 55 extremely preterm infants born between June 2017 and July 2018. Levels of 27 cytokines were measured in blood drawn from the umbilical artery at birth and from infants at 1-3 and 21-28 days of life. Placental pathology was grouped as normal (N), inflammation (I), vasculopathy (V), or combined vasculopathy and inflammation (V+I). Results: Complete data was available from 42 patients. Cord blood median levels of cytokines differed between groups with the highest levels observed in group V+I as compared to groups N, I and V for the following: Eotaxin (p = 0.038), G-CSF (p = 0.023), IFN-γ (p = 0.002), IL-1ra (p < 0.001), IL-4 (p = 0.005), IL-8 (p = 0.010), MCP-1 (p = 0.011), and TNFα (p = 0.002). Post-hoc analysis revealed sex differences between and within the placental pathology groups. Conclusion: Specific types of placental pathology may be associated with differential cytokine profiles in extremely pre-term infants. Sampling from cord blood may help assess the pathological status of the placenta and potentially infer outcome risks for the infant.

Management of clinical chorioamnionitis: an evidence-based approach

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

Epidural analgesia, intrapartum hyperthermia, and neonatal brain injury: a systematic review and meta-analysis

BACKGROUND

Epidural analgesia is associated with intrapartum hyperthermia, and chorioamnionitis is associated with neonatal brain injury. However, it is not known if epidural hyperthermia is associated with neonatal brain injury. This systematic review and meta-analysis investigated three questions: (1) does epidural analgesia cause intrapartum hyperthermia, (2) is intrapartum hyperthermia associated with neonatal brain injury, and (3) is epidural-induced hyperthermia associated with neonatal brain injury?

METHODS

PubMed, ISI Web of Knowledge, The Cochrane Library, and Embase were searched from inception to January 2020 using Medical Subject Headings (MeSH) terms relating to epidural analgesia, hyperthermia, labour, and neonatal brain injury. Studies were reviewed independently for inclusion and quality by two authors (Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach). Two meta-analyses were performed using the Mantel-Haenszel fixed effect method to generate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Forty-one studies were included for Question 1 (646 296 participants), 36 for Question 2 (11 866 021 participants), and two studies for Question 3 (297 113 participants). When the mode of analgesia was randomised, epidural analgesia was associated with intrapartum hyperthermia (OR: 4.21; 95% CI: 3.48-5.09). There was an association between intrapartum hyperthermia and neonatal brain injury (OR: 2.79; 95% CI: 2.54-2.3.06). It was not possible to quantify the association between epidural-induced hyperthermia and neonatal brain injury.

CONCLUSIONS

Epidural analgesia is a cause of intrapartum hyperthermia, and intrapartum hyperthermia of any cause is associated with neonatal brain injury. Further work is required to establish if epidural-induced hyperthermia is a cause of neonatal brain injury.

Histologic chorioamnionitis and risk of neurodevelopmental impairment at age 10 years among extremely preterm infants born before 28 weeks of gestation

BACKGROUND

Extremely preterm infants whose placenta had histologic evidence of chorioamnionitis have early brain dysfunction, but little is known about neurologic development at 10 years of age.

OBJECTIVE

We investigated the association between histologic chorioamnionitis and neurodevelopmental impairment at 10 years among children born <28 weeks' gestation (extremely preterm).

STUDY DESIGN

The multicenter Extremely Low Gestational Age Newborns study enrolled extremely preterm newborns from 2002 to 2004 at 14 hospitals in the United States. Chorioamnionitis was defined by histologic stage (early, moderate, and advanced) and grade (mild/moderate and severe) of chorionic plate and umbilical cord inflammation. The children were examined for cerebral palsy at 2 years and for autism spectrum disorder, cognitive impairment (intelligence quotient >2 standard deviations below the mean), and epilepsy at the age of 10 years by blinded evaluators using validated measures. Multivariable logistic regression with generalized estimating equations was used.

RESULTS

Among 805 placentas, 43% (347/805) had histologic chorioamnionitis by moderate or advanced maternal stage, 36% (286/805) by severe maternal grade, 18% (132/737) by moderate or advanced fetal stage, and 1% (10/737) by severe fetal grade. The frequencies of impairments were 11% (88/767) for cerebral palsy, 7% (56/773) for autism spectrum disorder, 15% (120/788) for cognitive impairment, and 7% (52/763) for epilepsy. After adjustment for maternal age, body mass index, race, insurance status, maternal education, tobacco use, infant sex, and multiple gestations, the adjusted odds ratio for the association between histologic chorioamnionitis and cerebral palsy years was increased with advanced maternal stage (adjusted odds ratio, 2.5; 95% confidence interval, 1.6-3.9), severe maternal grade (adjusted odds ratio, 2.0; 95% confidence interval, 1.2-3.4), moderate fetal stage (adjusted odds ratio, 2.20; 95% confidence interval, 2.1-2.2), and mild or moderate fetal grade (adjusted odds ratio, 1.5; 95% confidence interval, 1.0-2.2). Similarly, the adjusted odds ratio for the association between histologic chorioamnionitis and epilepsy was increased with advanced maternal stage (adjusted odds ratio, 1.5; 95% confidence interval, 1.3-1.6) and severe fetal grade (adjusted odds ratio, 5.9; 95% confidence interval, 1.9-17.8). In addition, the adjusted odds ratio for the association between histologic chorioamnionitis and autism spectrum disorder was increased with mild or moderate fetal grade (adjusted odds ratio, 1.7; 95% confidence interval, 1.0-2.9). Histologic chorioamnionitis was not associated with cognitive impairment. These findings held after adjustment for gestational age at delivery. In contrast to histologic chorioamnionitis, a clinical diagnosis of chorioamnionitis was not associated with neurodevelopmental impairment.

CONCLUSION

Histologic chorioamnionitis may be associated with some forms of neurodevelopmental impairment at 10 years of life among infants born <28 weeks' gestation.

Maternal inflammation leads to different mTORC1 activity varied by anatomic locations in mouse placenta†

Maternal inflammation (MI) is associated with many adverse perinatal outcomes. The placenta plays a vital role in mediating maternal-fetal resource allocation. Studies have shown that MI contributes to placental dysfunction, which then leads to adverse birth outcomes and high health risks throughout childhood. Placental mammalian target of rapamycin complex 1 (mTORC1) signaling pathway links maternal nutrient availability to fetal growth; however, the impact of MI on mTORC1 signaling in the placenta remains unclear. In this study, we sought to explore the changes of mTORC1 signaling in the mouse placenta at late gestation by using two models of MI employing lipopolysaccharide (LPS) and interleukin-1β (IL-1β) to mimic acute (aMI) and sub-chronic (cMI) inflammatory states, respectively. We determined placental mTORC1 activity by measuring the activity of mTORC1 downstream molecules, including S6k, 4Ebp1, and rpS6. In the aMI model, we found that mTORC1 activity was significantly decreased in the placental decidual and junctional zone at 2 and 6 h after LPS surgery, respectively; however, mTORC1 activity was significantly increased in the placental labyrinth zone at 2, 6, and 24 h after LPS treatment, respectively. In the cMI model, we observed that mTORC1 activity was increased only in the placental labyrinth zone after consecutive IL-1β exposure. Our study reveals that different parts of the mouse placenta react differently to MI, leading to variable mTORC1 activity throughout the placenta. This suggests that different downstream molecules of mTORC1 from different parts of the mouse placenta may be used in clinical research to monitor the fetal well-being during MI.

The Role of the Placenta in Perinatal Stroke: A Systematic Review

CONTEXT

Placental pathology may be an important missing link in the causal pathway of perinatal stroke. The study aim was to systematically review the literature regarding the role of the placenta in perinatal stroke. MEDLINE, Embase, Scopus, and Web of Science electronic databases were searched from 2000 to 2019. Studies were selected based on predefined criteria. To enable comparisons, placental abnormalities were coded using Redline's classification.

RESULTS

Ten studies met the inclusion criteria. Less than a quarter of stroke cases had placental pathology reported. Placental abnormalities were more common among children with perinatal stroke than in the control group. The most frequent placental abnormality was Redline's category 2 (thrombo-inflammatory process).

CONCLUSIONS

Placental abnormalities appear to be associated with perinatal stroke, supporting additional indirect evidence and biological plausibility of a causative role. However, the results should be interpreted cautiously considering the low frequency of placental examination and lack of uniformity in placental pathology reporting.

CLINICAL TRIAL REGISTRATION

PROSPERO Registration no: CRD42017081256.

Association between Placental Inflammatory Pathology and Offspring Neurodevelopment at 8 Months and 4 and 7 Years of Age

OBJECTIVE

To examine whether placental inflammatory pathology is associated with subsequent child neurodevelopment.

STUDY DESIGN

We used the data of US Collaborative Perinatal Project cohort study. Placentas were examined by pathologists and child neurodevelopment was evaluated at 8 months and 4 and 7 years of age. Multivariable logistic regression modelling was used to assess the association. A mediation analysis was used to evaluate whether the association was mediated through shorter gestational age.

RESULTS

Multivariable analysis after adjusting for confounders showed that placental inflammatory pathology was significantly associated with low Bayley motor (adjusted OR (aOR), 2.15; 95% CI, 1.50-3.06) and mental scales (aOR, 1.51; 95% CI, 1.05-2.17) at 8 months and an IQ of 70-84 (aOR, 1.13; 95% CI, 1.01-1.26) at 4 years of age. The association diminished at 7 years of age (IQ of <70, aOR 1.20 [95% CI, 0.97-1.48]; IQ of 70-79, aOR 1.03 [95% CI, 0.89-1.18]). The mediation analysis demonstrated that associations between placental inflammatory pathology and development were primarily due to direct effects of placental inflammatory pathology rather than indirect effects of shorter gestational age.

CONCLUSIONS

Placental inflammation was associated with adverse offspring neurodevelopment up to 4 years of age.

Is Stem Cell Therapy the New Savior for Cerebral Palsy Patients? A Review

Cerebral Palsy (CP) is one of the foremost causes of childhood motor disability and disrupts the individual's development and ability to function. Several factors contribute to the development of CP such as preterm delivery, low birth weight, infection/inflammation, and additional pregnancy complications, both in preterm and term infants. As there is no specific treatment for CP, rehabilitation is the current option for the management of patients. The serious nature of this condition creates deficits that last a lifetime. 

We collected studies that were published in the past 10 years, using PubMed as our main database. We chose studies that were relevant to CP and stem cell therapy. We mainly focused on various types of stem cells that can be used in treatment, mechanism of action (MOA) of stem cells, routes, dosage, and adverse effects, their efficacy, and safety in CP patients. Of all the 38 studies we reviewed, we found that five articles discussed the utilization of human umbilical cord blood [hUCB], four articles discussed autologous bone marrow stem cells, and one discussed allogeneic umbilical cord blood usage. One article discussed neural stem-like cells (NSLCs) derived from bone marrow and the remaining 27 articles were about CP and its treatment.

We reviewed detailed information about the possible stem cell therapies and their benefits in patients with CP. We found that immune modulation is the major mechanism of action of stem cells, and among all the types of stem cells. Autologous umbilical cord mesenchymal stem cells appear to be safe and most effective in treatment compared to other stem cell treatments. Among all symptoms, motor symptoms are best corrected by stem cell therapy. Still, it did not show any marked improvement in treating other symptoms like speech defects, sensory or cognitive defects, or visual impairment.

Early- and Late-Respiratory Outcome in Very Low Birth Weight with or without Intrauterine Inflammation

• IUI is a risk factor for spontaneous preterm birth and contributes to prematurity-associated mortality and morbidity.• HCA greatly affected Apgar's score and lung management of VLBWI at birth and later on with increased incidence of BPD.• HCA + FUN did not significantly impact on respiratory outcome.

OBJECTIVE

Intrauterine inflammation or infection (IUI) is a risk factor for spontaneous preterm birth and contributes to prematurity-associated mortality and morbidity. IUI can include inflammation, as well as infections of varying degrees of severity and duration. Histological chorioamnionitis (HCA) remains the "gold standard" for the diagnosis but clinical, microbiological, and biochemical criteria are often used to define chorioamnionitis. The impact of intrauterine inflammation on respiratory outcome, in infants with very low birth weight, is still unclear and previous data are conflicting showing increase, decrease, or no risk of respiratory complications.

STUDY DESIGN

This is a retrospective study aimed to investigate the role of IUI on neonatal respiratory outcome. Histological criteria (HCA alone and HCA + funisitis [FUN]) and "intrauterine inflammation or infection or both" "Triple I" definition were used; different management in delivery room, in the first 7 days of life (early outcome) and incidence of mild, moderate, and severe bronchopulmonary dysplasia (BPD; late outcome) were considered.

RESULTS

A total of 162 infants with very low birth weight (VLBW) with placenta histology were enrolled. Suspected TRIPLE or fever alone was present in 7.4%, and confirmed TRIPLE or HCA in 29.6% of cases (HCA alone 19.1% vs. HCA + FUN 10.5%). Preterm premature rupture of membrane (p-PROM) was strongly associated with HCA (66.6% in HCA group) and HCA was present in 80% neonates born between 22 and 24 weeks of gestational age (GA). HCA group (GA, 26 weeks; birth weight [BW], 880 g) showed lower Apgar's score, higher intubation rate, and need of ventilation in delivery room, surfactant, duration of noninvasive ventilation (NIV), severe patent ductus arteriosus (PDA), and incidence of BPD compared with no-HCA (GA, 30 weeks; BW, 1,210 g). Length of hospital stay and mortality were higher in HCA group (p = 0.01) and an increasing trend was present for HCA + FUN compared with HCA alone.

CONCLUSION

HCA greatly affected Apgar's score and lung management of VLBW infants (VLBWI) at birth and later on with increased incidence of BPD, thus impacting length of stay and quality of life, while HCA + FUN did not significantly impact on respiratory outcome. Further studies are needed to clarify the role of HCA and FUN in VLBW neonates.

Perinatal inflammation is associated with social and motor impairments in preterm children without severe neonatal brain injury

OBJECTIVE

To test the association between exposure to perinatal inflammation - i.e. clinical chorioamnionitis or early-onset neonatal infection - in preterm children without severe neonatal brain injury and neurodevelopmental outcome at 30 months of corrected age (CA).

DESIGN

Cross-sectional study from a French regional cohort of clinical follow-up (SEVE Network).

PATIENTS

One hundred sixty-four surviving neonates without severe brain injury - namely, grade III and IV cerebral hemorrhage and cystic periventricular leukomalacia - and without late-onset neonatal inflammation exposure - namely, late-onset neonatal infection and necrotizing enterocolitis -, born at less than 33 weeks of gestational age from November 2011 to June 2015 and enrolled in the SEVE Network.

MAIN OUTCOME MEASURE

Global developmental quotient (DQ) score of the revised Brunet-Lézine scale and its four indices measured by the same neuropsychologist at 30 months of CA.

RESULTS

After multivariate analysis, exposure to perinatal inflammation was not found significantly associated with a modification of the global DQ score (coefficient -1.7, 95% CI -4.8 to 1.3; p = 0.26). Exposure to perinatal inflammation was associated with a decrease of the gross motor function DQ score (coefficient -6.0, 95% CI -9.9 to -2.1; p < 0.01) and a decrease of the sociability DQ score (coefficient -5.1, 95% CI -9.2 to -0.9; p = 0.02). Language and visuospatial coordination DQ scores were not affected by exposure to perinatal inflammation.

CONCLUSION

Exposure to perinatal inflammation in preterm children without severe neonatal brain injury is independently associated with decreased motor and social abilities at 30 months of CA.

DNA Methylation Profile in Human Cord Blood Mononuclear Leukocytes From Term Neonates: Effects of Histological Chorioamnionitis

Background: Histological chorioamnionitis (HCA) is an infection/inflammation of fetal membranes and complicates 5.2-28.5% of all live births. Exposure to HCA can have long-term consequences including abnormal neurodevelopment and an increased risk for allergic disorders and asthma later in childhood. HCA may incite epigenetic changes, which have the potential to modulate both the immune and neurological systems as well as increase the risk of related disorders later in life. However, there is limited data on the impact of HCA on epigenetics, in particular DNA methylation, and changes to immune and neurological systems in full-term human neonates. Objective: To determine differential DNA methylation in cord blood mononuclear leukocytes from neonates exposed to HCA. Methods: Cord blood was collected from 10 term neonates (5 with HCA and 5 controls without HCA) and mononuclear leukocytes were isolated. Genome-wide DNA methylation screening was performed on Genomic DNA extracted from mononuclear leukocytes. Results: Mononuclear leukocytes from cord blood of HCA-exposed neonates showed differential DNA methylation of 68 probe sets compared to the control group (44 hypermethylated, 24 hypomethylated) with a p ≤ 0.0001. Several genes involved in immune modulation and nervous system development were found to be differentially methylated. Important canonical pathways as revealed by Ingenuity Pathway Analysis (IPA) were CREB Signaling in Neurons, FcγRIIB Signaling in B Lymphocytes, Cell Cycle: G1/S Checkpoint Regulation, Interleukin-1, 2, 3, 6, 8, 10, 17, and 17A signaling, p53 signaling, dopamine degradation, and serotonin degradation. The diseases and disorders picked up by IPA were nervous system development and function, neurological disease, respiratory disease, immune cell trafficking, inflammatory response, and immunological disease. Conclusions: HCA induces differential DNA methylation in cord blood mononuclear leukocytes. The differentially methylated genes may contribute to inflammatory, immunological and neurodevelopmental disorders in neonates exposed to HCA.

Neuroimaging findings associated with the fetal inflammatory response syndrome

The fetal inflammatory response syndrome (FIRS) is a condition whereby the fetus mounts an inflammatory response to intrauterine infection/inflammation. Clinical consequences include preterm premature rupture of membranes (PPROM), spontaneous preterm delivery, neonatal sepsis, bronchopulmonary dysplasia, and brain and other organ injury. Mechanisms leading to brain injury in FIRS have been investigated in animal and human studies. We review the neuroimaging findings of brain injury in FIRS, which overlap those of hypoxic-ischemic injury, and clinical correlation is necessary for a correct diagnosis. FIRS should be considered the primary diagnosis when neuroimaging findings such as periventricular leukomalacia are identified in preterm children born as a consequence of PPROM and spontaneous preterm labor. Additionally, FIRS should be considered in term infants who do not have the most common features of HIE (e.g. a sentinel event). Systematic histopathologic examination of the placenta and umbilical cord and/or detection of characteristic inflammatory markers in such cases are needed to establish the correct diagnosis.

Mechanisms of brain injury in newborn infants associated with the fetal inflammatory response syndrome

The fetal inflammatory response syndrome (FIRS) is characterized by umbilical cord inflammation and elevated fetal pro-inflammatory cytokines. Surviving neonates, especially very preterm infants, have increased rates of neonatal morbidity including neurodevelopmental impairment. The mechanism of brain injury in FIRS is complex and may involve "multiple hits." Exposure to in utero inflammation initiates a cascade of the fetal immune response, where pro-inflammatory cytokines can cause direct injury to oligodendrocytes and neurons. Activation of microglia results in further injury to vulnerable pre-myelinating oligodendrocytes and influences the integrity of the fetal and newborn's blood-brain barrier, resulting in further exposure of the brain to developmental insults. Newborns exposed to FIRS are frequently exposed to additional perinatal and postnatal insults that can result in further brain injury. Future directions should include evaluations for new therapeutic interventions aimed at reducing brain injury by dampening FIRS, inhibition of microglial activation, and regeneration of immature oligodendrocytes.

Association of Preeclampsia in Term Births With Neurodevelopmental Disorders in Offspring

IMPORTANCE

Preeclampsia during pregnancy has been linked to an increased risk of cerebral palsy in offspring. Less is known about the role of preeclampsia in other neurodevelopmental disorders.

OBJECTIVE

To determine the association between preeclampsia and a range of adverse neurodevelopmental outcomes in offspring after excluding preterm births.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, population-based cohort study included singleton children born at term from January 1, 1991, through December 31, 2009, and followed up through December 31, 2014 (to 5 years of age), using Norway's Medical Birth Registry and linked to other demographic, social, and health information by Statistics Norway. Data were analyzed from May 30, 2018, to November 17, 2019.

EXPOSURES

Maternal preeclampsia.

MAIN OUTCOMES AND MEASURES

Associations between preeclampsia in term pregnancies and cerebral palsy, attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), epilepsy, intellectual disability, and vision or hearing loss using multivariable logistic regression.

RESULTS

The cohort consisted of 980 560 children born at term (48.8% female and 51.2% male; mean [SD] gestational age, 39.8 [1.4] weeks) with a mean (SD) follow-up of 14.0 (5.6) years. Among these children, 28 068 (2.9%) were exposed to preeclampsia. Exposed children were at increased risk of ADHD (adjusted odds ratio [OR], 1.18; 95% CI, 1.05-1.33), ASD (adjusted OR, 1.29; 95% CI, 1.08-1.54), epilepsy (adjusted OR, 1.50; 95% CI, 1.16-1.93), and intellectual disability (adjusted OR, 1.50; 95% CI, 1.13-1.97); there was also an apparent association between preeclampsia exposure and cerebral palsy (adjusted OR, 1.30; 95% CI, 0.94-1.80).

CONCLUSIONS AND RELEVANCE

Preeclampsia is a well-established threat to the mother. Other than the hazards associated with preterm delivery, the risks to offspring from preeclampsia are usually regarded as less important. This study's findings suggest that preeclampsia at term may have lasting effects on neurodevelopment of the child.