The relation between cesarean birth and child cognitive development

Consumption of Different Combinations of Human Milk Oligosaccharides in the First 6 Months of Infancy is Positively Associated with Early Cognition at 2 Years of Age in a Longitudinal Cohort of Latino Children

BACKGROUND

Lactation has been widely associated with optimal neurocognitive development, but the underlying mechanism remains unknown. Human milk oligosaccharides (HMOs) are complex sugars that support brain development, but prior studies examining their associations with cognition have yielded inconsistent findings.

OBJECTIVE

To provide a broader understanding of how HMOs jointly influence cognition.

METHODS

We used data from an ongoing longitudinal cohort of Latino mother-infant dyads. Human milk samples from 1-month (n = 157) and 6-months (n = 107) postpartum were assessed for the 19 most abundant HMOs. Cognitive performance was assessed at 2-years using the Bayley Scale of Infant and Toddler Development. A partial least squares model identified HMO combinations predictive of cognitive scores.

RESULTS

At 1-month, the combination of higher levels of Lacto-N-neotetraose (LNnT), Lacto-N-tetraose (LNT), Lacto-N-fucopentaose III (LNFP-III), 6`Sialyllactose (6`SL), and 2`Fucosyllactose (2`FL) with lower levels of Sialyllacto-N-tetraose b (LSTb), Lacto-N-fucopentaose II (LNFP-II), Fucodisialyllacto-N-hexaose (FDSLNH), and 3-Fucosyllactose (3FL) significantly predicted higher cognitive scores (β = 0.61 [0.30, 0.92]), explaining an additional 8% of the variance over a model with only nuisance covariates (11%). Additional analyses revealed that the combination of higher LNFP-III and lower LSTb alone explained 5% more of the variation in cognitive scores (β = 0.66 [0.24, 1.09]). At 6-months (n = 107), higher LNnT, LNT, and LNFP-III and lower 3-fucosyllactose (3FL) and LSTb explained an extra 6% of the variance in cognitive scores (β = 0.43 [0.12 - 0.75]).

CONCLUSIONS

This study highlights specific HMO combinations in early life influencing cognitive performance at 2 years.

Impact of physical activity during pregnancy on infant neurodevelopment

OBJECTIVES

To investigate prospectively the impact of physical activity during pregnancy on infant neurodevelopment, considering relevant confounding factors, physical activity intensity and the trimester of pregnancy in which it is performed.

METHODS

Prospective follow-up study of 791 pregnant women from the first trimester of pregnancy to 40 days postpartum. Three intensity levels of physical activity were assessed in each trimester of pregnancy by the International Physical Activity Questionnaire (IPAQ). Infant neuro development was assessed at 40 days postpartum by the third edition of the Bayley Scales for Infant Development-Third Edition (BSID-III). Analysis adjusted by sociodemographics, anxiety symptoms, lifestyle habits, quality of diet, body mass index, postpartum depressive symptoms and mother-infant attachment.

RESULTS

ANCOVA analysis have shown that 40 days old infants of mothers in the moderate and high PA groups in the third trimester obtained 3.2 and 3.8 points higher scores respectively in the language total scale; and 4.1 and 5.1 points higher scores respectively in the motor total scale than infants of mothers in the low PAgroup.

CONCLUSION

Moderate to high intensity physical activity during pregnancy has a positive impact on infant neurodevelopment. More specific recommendations must be incorporated in international guidelines and into maternal education sessions to improve infants' neurodevelopment.

Effect of cesarean section on the risk of autism spectrum disorders/attention deficit hyperactivity disorder in offspring: a meta-analysis

PURPOSE

This study was conducted to investigate the relationship between cesarean section (CS) offspring and autism spectrum disorders (ASD)/attention deficit hyperactivity disorder (ADHD).

METHODS

Searching of the databases (PubMed, Web of Science, Embase, and Cochrane Library) for studies on the relationship between mode of delivery and ASD/ADHD until August 2022. The primary outcome was the incidence of ASD/ADHD in the offspring.

RESULTS

This meta-analysis included 35 studies (12 cohort studies and 23 case-control studies). Statistical results showed a higher risk of ASD (odds ratio (OR) = 1.25, P < 0.001) and ADHD (OR = 1.11, P < 0.001) in CS offspring compared to the VD group. Partial subgroup analysis showed no difference in ASD risk between CS and VD offspring in sibling-matched groups (OR = 0.98, P = 0.625). The risk of ASD was higher in females (OR = 1.66, P = 0.003) than in males (OR = 1.17, P = 0.004) in the CS offspring compared with the VD group. There was no difference in the risk of ASD between CS under regional anesthesia group and VD group (OR = 1.07, P = 0.173). However, the risk of ASD was higher in the CS offspring under general anesthesia than in the VD offspring (OR = 1.62, P < 0.001). CS offspring developed autism (OR = 1.38, P = 0.011) and pervasive developmental disorder-not otherwise specified (OR = 1.46, P = 0.004) had a higher risk than VD offspring, but there was no difference in Asperger syndrome (OR = 1.19, P = 0.115). Offspring born via CS had a higher incidence of ADHD in different subgroup analyses (sibling-matched, type of CS, and study design).

CONCLUSIONS

In this meta-analysis, CS was a risk factor for ASD/ADHD in offspring compared with VD.

Early brain microstructural development among preterm infants requiring caesarean section versus those delivered vaginally

It is known that the rate of caesarean section (C-section) has been increasing among preterm births. However, the relationship between C-section and long-term neurological outcomes is unclear. In this study, we utilized diffusion tensor imaging (DTI) to characterize the association of delivery method with brain white matter (WM) microstructural integrity in preterm infants. We retrospectively analyzed the DTI scans and health records of preterm infants without neuroimaging abnormality on pre-discharge term-equivalent MRI. We applied both voxel-wise and tract-based analyses to evaluate the association between delivery method and DTI metrics across WM tracts while controlling for numerous covariates. We included 68 preterm infants in this study (23 delivered vaginally, 45 delivered via C-section). Voxel-wise and tract-based analyses revealed significantly lower fractional anisotropy values and significantly higher diffusivity values across major WM tracts in preterm infants delivered via C-section when compared to those delivered vaginally. These results may be partially, but not entirely, mediated by lower birth weight among infants delivered by C-section. Nevertheless, these infants may be at risk for delayed neurodevelopment and could benefit from close neurological follow up for early intervention and mitigation of adverse long-term outcomes.

Cesarean section induced dysbiosis promotes type 2 immunity but not oxazolone-induced dermatitis in mice

Delivery by cesarean section (CS) is associated with an altered gut microbiota (GM) colonization and a higher risk of later chronic inflammatory diseases. Studies investigating the association between CS and atopic dermatitis (AD) are contradictive and often biased by confounding factors. The aim of this study was therefore to provide experimental evidence for the association between CS and AD in a mouse model and clarify the role of the GM changes associated with CS. It was hypothesized that CS-delivered mice, and human CS-GM transplanted mice develop severe dermatitis due to early dysbiosis. BALB/c mice delivered by CS or vaginally (VD) as well as BALB/c mice transplanted with GM from CS or VD human donors were challenged with oxazolone on the ear. The severity of dermatitis was evaluated by ear thickness and clinical and histopathological assessment which were similar between all groups. The immune response was assessed by serum IgE concentration, local cytokine response, and presence of immune cells in the draining lymph node. Both CS-delivered mice and mice inoculated with human CS-GM had a higher IgE concentration. A higher proportion of Th2 cells were also found in the CS-GM inoculated mice, but no differences were seen in the cytokine levels in the affected ears. In support of the experimental findings, a human cohort analysis from where the GM samples were obtained found that delivery mode did not affect the children's risk of developing AD. In conclusion, CS-GM enhanced a Th2 biased immune response, but had no effect on oxazolone-induced dermatitis in mice.

Early brain microstructural development among preterm infants requiring caesarean section versus those delivered vaginally

It is known that the rate of caesarean section (C-section) has been increasing among preterm births. However, the relationship between C-section and long-term neurological outcomes is unclear. In this study, we utilized diffusion tensor imaging (DTI) to characterize the association of delivery method with brain white matter (WM) microstructural integrity in preterm infants. We retrospectively analyzed the DTI scans and health records of preterm infants without neuroimaging abnormality on pre-discharge term-equivalent MRI. We applied both voxel-wise and tract-based analyses to evaluate the association between delivery method and DTI metrics across WM tracts while controlling for numerous covariates. We included 68 preterm infants in this study (23 delivered vaginally, 45 delivered via C-section). Voxel-wise and tract-based analyses revealed significantly lower fractional anisotropy values and significantly higher diffusivity values across major WM tracts in preterm infants delivered via C-section when compared to those delivered vaginally. These results may be partially, but not entirely, mediated by lower birth weight among infants delivered by C-section. Nevertheless, these infants may be at risk for delayed neurodevelopment and could benefit from close neurological follow up for early intervention and mitigation of adverse long-term outcomes.

Association between Cesarean section and neurodevelopmental disorders in a Japanese birth cohort: the Japan Environment and Children's Study

BACKGROUND

The long-term effects of a Cesarean section (CS) birth on child neurodevelopment are of increasing interest. In this study, we examined the associations between mode of delivery and presence of neurodevelopmental disorders in toddlers. Moreover, given that the prevalence of several neurodevelopmental disorders such as autism spectrum disorder (ASD) is known to differ by sex, we also investigated these associations separately in male and female toddlers.

METHODS

We investigated 65,701 mother-toddler pairs from the Japan Environment and Children's Study, a nationally representative children's cohort study. To investigate the associations between mode of delivery (CS or vaginal delivery) and neurodevelopmental disorders (motor delay, intellectual disability, and ASD) in 3-year-old toddlers as a whole and stratified by sex, we used logistic regression models to calculate adjusted odds ratios (aORs) with 95% confidence intervals (CIs).

RESULTS

The morbidity of ASD at age 3 years was higher for children delivered by CS than those delivered vaginally (aOR 1.38, 95% CI 1.04-1.83). However, no such difference was evident in the case of motor delay or intellectual disability (aOR 1.33, 95% CI 0.94-1.89; aOR 1.18, 95% CI 0.94-1.49, respectively). In the analysis by sex, CS was not associated with increased risk of any of the neurodevelopmental disorders in males, but it was associated with increased risks of motor delay (aOR 1.88, 95% CI 1.02-3.47) and ASD (aOR 1.82, 95% CI 1.04-3.16) in females.

CONCLUSIONS

This study provides evidence of significant associations between mode of delivery and neurodevelopmental disorders in early childhood. Females may be more sensitive to the effects of CS than males.

Signalling cognition: the gut microbiota and hypothalamic-pituitary-adrenal axis

Cognitive function in humans depends on the complex and interplay between multiple body systems, including the hypothalamic-pituitary-adrenal (HPA) axis. The gut microbiota, which vastly outnumbers human cells and has a genetic potential that exceeds that of the human genome, plays a crucial role in this interplay. The microbiota-gut-brain (MGB) axis is a bidirectional signalling pathway that operates through neural, endocrine, immune, and metabolic pathways. One of the major neuroendocrine systems responding to stress is the HPA axis which produces glucocorticoids such as cortisol in humans and corticosterone in rodents. Appropriate concentrations of cortisol are essential for normal neurodevelopment and function, as well as cognitive processes such as learning and memory, and studies have shown that microbes modulate the HPA axis throughout life. Stress can significantly impact the MGB axis via the HPA axis and other pathways. Animal research has advanced our understanding of these mechanisms and pathways, leading to a paradigm shift in conceptual thinking about the influence of the microbiota on human health and disease. Preclinical and human trials are currently underway to determine how these animal models translate to humans. In this review article, we summarize the current knowledge of the relationship between the gut microbiota, HPA axis, and cognition, and provide an overview of the main findings and conclusions in this broad field.

Associations between maternal folate status and choline intake during pregnancy and neurodevelopment at 3-4 years of age in the Alberta Pregnancy Outcomes and Nutrition (APrON) study

Folate and choline are methyl donor nutrients that may play a role in fetal brain development. Animal studies have reported that prenatal folate and choline supplementation are associated with better cognitive outcomes in offspring and that these nutrients may interact and affect brain development. Human studies that have investigated associations between maternal prenatal folate or choline levels and neurodevelopmental outcomes have reported contradictory findings and no human studies have examined the potential interactive effect of folate and choline on children's neurodevelopment. During the second trimester of pregnancy, maternal red blood cell folate was measured from blood samples and choline intake was estimated using a 24-h dietary recall in 309 women in the APrON cohort. At 3-5 years of age, their children's neurodevelopment was assessed using the Wechsler Preschool and Primary Scales of Intelligence - Fourth EditionCND, NEPSY-II language and memory subtests, four behavioral executive function tasks, and the Movement Assessment Battery for Children - Second Edition. Adjusted regressions revealed no associations between maternal folate and choline levels during pregnancy and most of the child outcomes. On the Dimensional Change Card Sort, an executive function task, there was an interaction effect; at high levels of choline intake (i.e., 1 SD above the mean; 223.03 mg/day), higher maternal folate status was associated with decreased odds of receiving a passing score (β = -0.44; 95%CI -0.81, -0.06). In conclusion, maternal folate status and choline intake during the second trimester of pregnancy were not associated with children's intelligence, language, memory, or motor outcomes at 3-4 years of age; however, their interaction may have an influence children's executive functions.

Gut Microbiome-Brain Alliance: A Landscape View into Mental and Gastrointestinal Health and Disorders

Gut microbiota includes a vast collection of microorganisms residing within the gastrointestinal tract. It is broadly recognized that the gut and brain are in constant bidirectional communication, of which gut microbiota and its metabolic production are a major component, and form the so-called gut microbiome-brain axis. Disturbances of microbiota homeostasis caused by imbalance in their functional composition and metabolic activities, known as dysbiosis, cause dysregulation of these pathways and trigger changes in the blood-brain barrier permeability, thereby causing pathological malfunctions, including neurological and functional gastrointestinal disorders. In turn, the brain can affect the structure and function of gut microbiota through the autonomic nervous system by regulating gut motility, intestinal transit and secretion, and gut permeability. Here, we examine data from the CAS Content Collection, the largest collection of published scientific information, and analyze the publication landscape of recent research. We review the advances in knowledge related to the human gut microbiome, its complexity and functionality, its communication with the central nervous system, and the effect of the gut microbiome-brain axis on mental and gut health. We discuss correlations between gut microbiota composition and various diseases, specifically gastrointestinal and mental disorders. We also explore gut microbiota metabolites with regard to their impact on the brain and gut function and associated diseases. Finally, we assess clinical applications of gut-microbiota-related substances and metabolites with their development pipelines. We hope this review can serve as a useful resource in understanding the current knowledge on this emerging field in an effort to further solving of the remaining challenges and fulfilling its potential.

Association between birth by caesarian section and anxiety, self-harm: a gene-environment interaction study using UK Biobank data

BACKGROUND

Limited efforts have been paid to explore the underlying genetic mechanisms of birth by caesarian section (CS) affecting the risks of adult anxiety and self-harm.

METHODS

Using UK Biobank cohort, the logistic regression model was first applied to evaluate the associations of adult anxiety and self-harm with birth by CS. Using birth by CS as exposure variables, genome-wide by environment interaction study (GWEIS) was then applied by PLINK2.0 to identify associated genes interacting with birth by CS for anxiety and self-harm.

RESULTS

In the observational study, significant associations were observed between birth by CS and anxiety (odds ratio (OR) = 1.24; 95% confidence interval (CI), 1.12-1.38; P = 4.86 × 10^- 5), and self-harm (OR = 1.12; 95% CI, 1.01-1.24; P = 2.90 × 10^- 2). GWEIS revealed multiple suggestive genes interacted with birth by CS for anxiety, such as DKK2 (rs13137764, P = 1.24 × 10^- 9, adjusted P = 2.68 × 10^- 7) and ATXN1 (rs62389045, P = 4.38 × 10^- 8, adjusted P = 3.55 × 10^- 6). For self-harm, significant gene-environment interactions of birth by CS on self-harm were detected, such as ALDH1A2 (rs77828167, P = 1.62 × 10^- 8; rs116899929, P = 1.92 × 10^- 8) and DAB1 (rs116124269, P = 3.20 × 10^- 8; rs191070006, P = 3.63 × 10^- 8).

CONCLUSIONS

Our results suggested that birth by CS was associated with the risk of adult anxiety and self-harm. We also discovered some genes interacted with birth by CS might influence the risk of anxiety and self-harm, which may provide novel clues for the pathogenesis of those mental disorders.

Impact of Gut Microbiota in Brain Ageing: Polyphenols as Beneficial Modulators

Brain ageing is a complex physiological process that includes several mechanisms. It is characterized by neuronal/glial dysfunction, alterations in brain vasculature and barriers, and the decline in brain repair systems. These disorders are triggered by an increase in oxidative stress and a proinflammatory state, without adequate antioxidant and anti-inflammatory systems, as it occurs in young life stages. This state is known as inflammaging. Gut microbiota and the gut–brain axis (GBA) have been associated with brain function, in a bidirectional communication that can cause loss or gain of the brain’s functionality. There are also intrinsic and extrinsic factors with the ability to modulate this connection. Among the extrinsic factors, the components of diet, principally natural components such as polyphenols, are the most reported. The beneficial effects of polyphenols in brain ageing have been described, mainly due to their antioxidants and anti-inflammatory properties, including the modulation of gut microbiota and the GBA. The aim of this review was, by following the canonical methodology for a state-of-the-art review, to compose the existing evidenced picture of the impact of the gut microbiota on ageing and their modulation by polyphenols as beneficial molecules against brain ageing.

Time trends in caesarean section rates and associations with perinatal and neonatal health: a population-based cohort study of 1 153 789 births in Norway

OBJECTIVES

To study caesarean section (CS) rates and associations with perinatal and neonatal health in Norway during 1999-2018.

DESIGN

Population-based cohort study.

SETTING

Medical Birth Registry of Norway.

PARTICIPANTS

1 153 789 births and 1 174 066 newborns.

METHODS

CS, intrapartum, perinatal and neonatal mortality rates expressed as percentages (%) or per mille (‰) with 95% CIs.

PRIMARY AND SECONDARY OUTCOME MEASURES

CS rates in the Robson Ten-Group Classification System; intrapartum, perinatal and neonatal mortality rates.

RESULTS

The overall CS rate increased from 12.9% in 1999 to 16.7% in 2008 (p<0.001), and then reduced to 15.8% in 2018 (p<0.001). The largest reductions were observed in Robson groups 2 and 4. In Robson group 2, the planned CS rate decreased from 9.6% in 2007-2008 to 4.6% in 2017-2018, the intrapartum CS rate decreased from 26.6% in 2007-2008 to 22.3% in 2017-2018. In Robson group 4, the planned CS rate decreased from 16.1% in 2007-2008 to 7.6% in 2017-2018, and the intrapartum CS rate decreased from 7.8% in 2007-2008 to 5.2% in 2017-2018.The intrapartum fetal mortality rate decreased from 0.51 per 1000 (‰) in 1999-2000 to 0.14‰ in 2017-2018. Neonatal mortality decreased from 2.52‰ to 1.58‰.

CONCLUSIONS

CS rates in Norway increased between 1999 and 2008, followed by a significant reduction between 2008 and 2018. At the same time, fetal and neonatal mortality rates decreased. Norwegian obstetricians and midwives have contributed to maintaining a low CS rate under 17%. These findings indicate that restricting the use of CS is a safe option for perinatal health.

Nascer de cesariana e associação com quociente de inteligência em adolescentes: contribuição do Consórcio de Coortes RPS (Ribeirão Preto, Pelotas e São Luís), Brasil

O objetivo do estudo foi avaliar a associação entre a cesariana e o quociente de inteligência (QI) em adolescentes do Município de São Luís, Maranhão, Brasil. Trata-se de um estudo longitudinal utilizando dados da coorte de nascimento em São Luís, iniciado no ano de 1997. A abordagem ocorreu na terceira fase da coorte, em 2016, com adolescente aos 18 e 19 anos de idade. A variável de exposição foi a via de nascimento e a variável de desfecho foi o QI, mensurada a partir da aplicação da terceira versão da Escala de Inteligência Wechsler para Adultos (WAIS-III). Na análise dos dados verificou-se a média do QI segundo as covariáveis e utilizou-se a regressão linear multivariada. Para controlar os fatores de confundimento foi elaborado um modelo teórico utilizando o gráfico acíclico dirigido. As variáveis confundidoras foram as socioeconômicas no momento do nascimento e as variáveis perinatais. A média do QI dos adolescentes foi 101,4. Na análise bruta, o QI dos adolescentes nascidos de cesariana foi 5,8 pontos maior em relação aos nascidos de parto vaginal (IC95%: 3,8; 7,7, p ≤ 0,001), com significância estatística. Na análise multivariada, o valor reduziu para 1,9 (IC95%: -0,5; 3,6, p = 0,141), sem significância estatística. O resultado do estudo mostrou que a cesariana não está associada ao QI dos adolescentes nessa amostra e reflete que as diferenças encontradas podem ser explicadas por outros fatores, como aspectos socioeconômicos e perinatais.

Cesarean Section and Child Development at 3 Years: A Prospective Cohort Study of First Births in Pennsylvania

OBJECTIVES

The rising cesarean birth rate globally has led to increasing concern about long-term unintended consequences, with particular focus on child neurodevelopmental outcomes. This study investigated the association between cesarean birth and early child neurodevelopment, measured at 3 years of age.

METHODS

This was a large multicenter longitudinal prospective cohort study of first-time mothers and their offspring in Pennsylvania. Mothers completed adapted versions of two measures of child development at 36- months postpartum: the modified Parents' Evaluation of Developmental Status (M-PEDS) and a shortened Ages and Stages Questionnaire (S-ASQ). Logistic regression models were used to assess the association between mode of delivery and delayed child development, controlling for confounding variables.

RESULTS

There were 695 (29.3%) children born by cesarean delivery and 1676 (70.7) born vaginally. Children born by cesarean had increased odds of scoring as developmentally delayed on both measures of child development: the M-PEDS (8.9% cesarean and 5.1% vaginal, adjusted odds ratio [aOR] = 1.58, 95% confidence interval [CI] = 1.11-2.24)) and the S-ASQ (6.3% cesarean and 3.3% vaginal, aOR = 1.66, 95% CI = 1.09-2.54). Additional factors associated with developmental delay were male sex, and the maternal factors of high pre-pregnancy body mass index, thyroid disorder, and diabetes.

CONCLUSION

In this large prospective cohort study of first-time mothers and their offspring, cesarean delivery was found to be associated with an elevated risk of delayed child development at age 3 years. This analysis highlights the importance of continued research to understand the impact of cesarean delivery on child development.

Cross-sectional observational study protocol: missing microbes in infants born by caesarean section (MiMIC): antenatal antibiotics and mode of delivery

INTRODUCTION

The intestinal microbiome in early life plays a major role in infant health and development. Factors like antibiotic exposure, breast/formula feeding and mode of delivery are known to affect the microbiome. The increasing occurrence of caesarean section (C-section) deliveries and antibiotic exposure warrants further insight into the potential missing microbes in those infants. The study objective is to study the effect of maternal antibiotic administration during pregnancy and/or C-section mode of delivery on the development of the infant's intestinal microbiome until the age of 2 years.

METHODS AND ANALYSIS

A single site, cross-sectional observational study of C-section and vaginally delivered infants being either exposed to maternal antibiotic treatment or not during the third trimester of pregnancy. Throughout the nine visits, stool, urine, saliva, hair, breast milk and vaginal swabs will be collected from either mother and/or infant for microbiome and metabolomic analysis.

ETHICS AND DISSEMINATION

The protocol was approved by the Clinical Research Ethics Committee of the Cork Teaching Hospitals. The trial has been registered at ClinicalTrials.gov.The findings from this study will be disseminated in peer-reviewed journals, during scientific conferences, and directly to the study participants. Sequencing data will be deposited in public databases.

TRIAL REGISTRATION NUMBER

NCT04134819.

Caesarean Section in Indonesia: Analysis of Trends and Socio-Demographic Correlates in Three Demographic and Health Surveys (2007–2017)

Objectives

This study determined the prevalence and trends in caesarean section (C-section) deliveries and the factors associated with the utilization of C-section deliveries among Indonesian mothers from 2007 to 2017.

Methods

We used Indonesia Demographic and Health Survey data sets (2007, 2012, and 2017) to assess the prevalence, trends, and factors associated with C-section delivery through univariate, bivariate, and multivariate analyses.

Results

A 10% increase in C-section delivery among Indonesian women was observed between the years 2007 and 2017. Mothers from urban areas tended to receive more C-sections than mothers from rural areas (adjusted odds ratio (aOR) = 1.49). More educated mothers were more likely (aOR = 3.373) to receive C-sections than mothers without formal education. Mothers from wealthy family backgrounds were more (aOR = 1.97) likely to receive C-sections than mothers from low-income families. Antenatal care (ANC) visits were significantly positively associated with receiving C-sections; mothers with more than four ANC visits (aOR = 4.54) tended to receive more C-sections than mothers with no ANC visits. For first births, mothers over 25 years of age were more likely (aOR = 2.07) to receive C-sections than mothers less than 18 years of age.

Conclusion

The percentage of C-sections has alarmingly increased. Thus, authorities in Indonesia should consider these findings and take necessary steps to decrease C-sections. The results of this study should help policymakers formulate appropriate policies that will encourage regular delivery where most appropriate.

THYROID DYSFUNCTION IN PREGNANCY: COMPARISON OF OUTCOMES IN INFANTS

The aim of this study was to compare the incidence of mild psychomotor delay in infants whose mothers were treated for thyroid dysfunction regardless of the cause during first trimester of pregnancy with those whose mothers did not use medications prenatally. The sample included 200 infants up to 4 months of age. Half of the infants were examined by a pediatric physiatrist, while the other half were chosen randomly from the primary pediatric clinic. Binary logistic regression was performed to assess the impact of factors on psychomotor delay. The model contained seven independent variables derived from bivariate analyses and clinical relevance. Results showed that the infant's chance of having psychomotor delay was 5.53 times higher if the mother had drug-compensated thyroid dysfunction. Younger gestational age increased the likelihood of delay 2.12 times per each gestational week. The likelihood of psychomotor delay also rose by 1% per 1 g of birth weight reduction. We found strong positive linear correlation between maternal drug-compensated thyroid dysfunction during pregnancy and psychomotor delay in infants, which has not been reported elsewhere. This differentiates an important and common prenatal risk factor and lays the foundation for faster initiation of habilitation of infants at risk. These insights provide a basis for planning the National Screening Program for Neurorisk Infants.

Intersections of the microbiome and early neurodevelopment

Our resident microbes influence nearly all aspects of our biological systems. In particular, the maternal and early life microbiota is uniquely positioned to influence the development of the nervous system, and alterations to the gut microbiota, or dysbiosis, during this critical time in early life can have long-lasting negative effects on health. The question of how the maternal and early life microbiota shapes neurodevelopment is the topic of numerous investigations. Here, we discuss two possible, but not necessarily independent, hypotheses: (1) the maternal microbiota during pregnancy regulates the metabolites that are important for fetal development, (2) maternal microbiota seeded to offspring at birth and early postnatal days programs offspring immune and brain development, and regulates key molecules for postnatal brain development. In this chapter, we provide an overview of the impact of the microbiota on brain and behavior, introduce the maternal gut and vaginal microbiome during pregnancy, and discuss current understandings of microbiome in the context of developmental origins of health and disease. We consider novel translational insights that harness the multitude of microbes and microbial metabolites for prevention or treatment of neurological disorders.

Obesity and the Brain

Innate and adaptive immunity are essential for neurodevelopment and central nervous system (CNS) homeostasis; however, the fragile equilibrium between immune and brain cells can be disturbed by any immune dysregulation and cause detrimental effects. Accumulating evidence indicates that, despite the blood-brain barrier (BBB), overactivation of the immune system leads to brain vulnerability that increases the risk of neuropsychiatric disorders, particularly upon subsequent exposure later in life. Disruption of microglial function in later life can be triggered by various environmental and psychological factors, including obesity-driven chronic low-grade inflammation and gut dysbiosis. Increased visceral adiposity has been recognized as an important risk factor for multiple neuropsychiatric conditions. The review aims to present our current understanding of the topic.

Animal Models for Assessing Impact of C-Section Delivery on Biological Systems

There has been a significant increase in Caesarean section (C-section) births worldwide over the past two decades and although it is can be a life-saving procedure, the enduring effects on host physiology are now undergoing further scrutiny. Indeed, epidemiological data have linked C-section birth with multiple immune, metabolic and neuropsychiatric diseases. Birth by C-section is known to alter the colonisation of the neonatal gut microbiota (with C-section delivered infants lacking vaginal microbiota associated with passing along the birth canal), which in turn can impact the development and maintenance of many important biological systems. Appropriate animal models are key to disentangling the role of missing microbes in brain health and disease in C-section births. In this review of preclinical studies, we interrogate the effects of C-section birth on the development (and maintenance) of several biological systems and we discuss the involvement of the gut microbiome on C-section-related alterations.

Maternal and early life exposures and their potential to influence development of the microbiome

At the dawn of the twentieth century, the medical care of mothers and children was largely relegated to family members and informally trained birth attendants. As the industrial era progressed, early and key public health observations among women and children linked the persistence of adverse health outcomes to poverty and poor nutrition. In the time hence, numerous studies connecting genetics ("nature") to public health and epidemiologic data on the role of the environment ("nurture") have yielded insights into the importance of early life exposures in relation to the occurrence of common diseases, such as diabetes, allergic and atopic disease, cardiovascular disease, and obesity. As a result of these parallel efforts in science, medicine, and public health, the developing brain, immune system, and metabolic physiology are now recognized as being particularly vulnerable to poor nutrition and stressful environments from the start of pregnancy to 3 years of age. In particular, compelling evidence arising from a diverse array of studies across mammalian lineages suggest that modifications to our metagenome and/or microbiome occur following certain environmental exposures during pregnancy and lactation, which in turn render risk of childhood and adult diseases. In this review, we will consider the evidence suggesting that development of the offspring microbiome may be vulnerable to maternal exposures, including an analysis of the data regarding the presence or absence of a low-biomass intrauterine microbiome.

Altered stress responses in adults born by Caesarean section

Birth by Caesarean-section (C-section), which increases the risk for metabolic and immune disorders, disrupts the normal initial microbial colonisation of the gut, in addition to preventing early priming of the stress and immune-systems.. Animal studies have shown there are enduring psychological processes in C-section born mice. However, the long-term impact of microbiota-gut-brain axis disruptions due to birth by C-section on psychological processes in humans is unknown. Forty age matched healthy young male university students born vaginally and 36 C-section delivered male students were recruited. Participants underwent an acute stressor, the Trier social stress test (TSST), during a term-time study visit. A subset of participants also completed a study visit during the university exam period, representing a naturalistic stressor. Participants completed a battery of cognitive tests and self-report measures assessing mood, anxiety, and perceived stress. Saliva, blood, and stool samples were collected for analysis of cortisol, peripheral immune profile, and the gut microbiota. Young adults born by C-section exhibit increased psychological vulnerability to acute stress and a prolonged period of exam-related stress. They did not exhibit an altered salivary cortisol awakening response to the TSST, but their measures of positive affect were significantly lower than controls throughout the procedure. Both C-section and vaginally-delivered participants performed equally well on cognitive assessments. Most of the initial effects of delivery mode on the gut microbiome did not persist into adulthood as the gut microbiota profile showed modest changes in composition in adult vaginally-delivered and C-sectioned delivered subjects. From an immune perspective, concentrations of IL-1β and 1L-10 were higher in C-section participants. These data confirm that there is a potential enduring effect of delivery mode on the psychological responses to acute stress during early adulthood. The mental health implications of these observations require further study regarding policies on C-section use.

The association of cesarean section with overweight and neurodevelopment of Chinese children aged 1-5 months

OBJECTIVE

The purpose of this survey was to explore the association of delivery mode with overweight and neurodevelopment of Chinese infants aged 1-5 months.

MATERIALS AND METHODS

This study was based on a cross-sectional survey. Data for this study were obtained from the Children's Nutrition and Health System Survey in China which was conducted from 2019 to 2020. Characteristics of parents and children and the delivery mode were obtained using interview-administered questionnaires. Body mass index-for age z-score (BMI z) was calculated using World Health Organization (WHO) child growth standards. Children's neurodevelopment was assessed by a trained child health care physician using the Child Psychological Development Scale. The association of delivery mode with infant overweight was analyzed using a multivariable logistic regression model. We conducted a multivariable linear regression model to explore the relationship between delivery modes with neurodevelopment.

RESULTS

In total, the present analysis included 1,347 children aged 1-5 months, 35.61% were born via cesarean section, of which 15.21% were overweight. After adjustment for infant characteristics and parental factors, the cesarean section was significantly related with the likehood of being overweight [OR = 1.95; 95% confidence interval (CI): 1.27 to 2.98]. Children born via cesarean section had a 3.41-point decrease in gross motor development (β = -3.41; 95% CI: -5.77 to -1.05), a 3.65-point decrease in fine motor development (β = -3.65; 95% CI: -6.03 to -1.28), and a 2.96-point in language development (β = -2.96; 95% CI: -5.20 to -0.73), a 1.65-point in total development (β = -1.65; 95% CI: -3.17 to -0.14) compared with those who were vaginal birth.

CONCLUSION

In our study population, cesarean section was associated with overweight and neurodevelopment outcomes. The cesarean section might increase the likehood of infant overweight, and might decrease the developmental scores of gross motor, fine motor and language. Further studies should be conducted to verify the associations and explore the possible mechanisms.

The First 1000 Days: Assembly of the Neonatal Microbiome and Its Impact on Health Outcomes

Early life microbial colonization is critical for the development of the immune system, postnatal growth, and long-term health and disease. The dynamic and nascent microbiomes of children are highly individualized and are characterized by low bacterial diversity. Any disruptions in microbial colonization can contribute to shifts in normal microbial colonization that persist past the first 1000 days of life and result in intestinal dysbiosis. Here, we focus on microbiome-host interactions during fetal, newborn, and infant microbiome development. We summarize the roles of bacterial communities in fetal development and adverse health outcomes due to dysbiosis. We also discuss how internal and external factors program the microbiome's metabolic machinery as it evolves into an adult-like microbiome. Finally, we discuss the limits of current studies and future directions. Studies on the early-life microbiome will be critical for a better understanding of childhood health and diseases, as well as restorative methods for the prevention and treatment of diseases in adulthood.

Cesarean birth elicits long-term effects on vasopressin and oxytocin neurons in the hypothalamic paraventricular nucleus of mice

Birth is an extraordinary event for placental mammals and occurs at a time when key developmental processes are shaping the brain. Remarkably, little is known about the contributions of birth to brain development and whether birth mode (vaginal vs. Cesarean) alters neurodevelopmental trajectories. We previously reported that Cesarean birth reduces vasopressin (VP) neuron number in the hypothalamic paraventricular nucleus (PVN) of mice at weaning. In this study, we investigated whether this effect extends to adulthood and whether birth mode affects oxytocin (OT) neurons, which are another prominent population in the PVN. We found that Cesarean-born adults had fewer VP neurons in the PVN, specifically in magnocellular regions. Interestingly, these regions also had more dying cells following a Cesarean birth, suggesting that cell death may be the underlying mechanism. The PVN of Cesarean-born adults also had smaller VP neuron somas and reduced VP efferent projections. Additionally, Cesarean-born mice showed fewer and smaller OT neurons in the PVN, but these effects were less robust than for VP neurons. We also examined VP and OT neuron number in the supraoptic and suprachiasmatic nuclei but found no effect of birth mode in these regions. Thus, Cesarean birth causes long-term effects on the VP and, to a lesser extent, OT systems in the PVN, suggesting that this region is particularly sensitive to the effects of birth mode. Our findings may help explain the social deficits reported for Cesarean-born mice, and are also of clinical significance given the widespread practice of Cesarean births across the world.

Role of Maternal Microbiota and Nutrition in Early-Life Neurodevelopmental Disorders

The rise in the prevalence of obesity and other related metabolic diseases has been paralleled by an increase in the frequency of neurodevelopmental problems, which has raised the likelihood of a link between these two phenomena. In this scenario, maternal microbiota is a possible linking mechanistic pathway. According to the “Developmental Origins of Health and Disease” paradigm, environmental exposures (in utero and early life) can permanently alter the body’s structure, physiology, and metabolism, increasing illness risk and/or speeding up disease progression in offspring, adults, and even generations. Nutritional exposure during early developmental stages may induce susceptibility to the later development of human diseases via interactions in the microbiome, including alterations in brain function and behavior of offspring, as explained by the gut–brain axis theory. This review provides an overview of the implications of maternal nutrition on neurodevelopmental disorders and the establishment and maturation of gut microbiota in the offspring.

Delivery Mode and Child Development at 20 Months of Age and 7 Years of Age in the Republic of Seychelles

OBJECTIVE

To determine if cesarean delivery is adversely associated with child neurodevelopment as measured at 20 months and 7 years.

METHODS

In a prospective cohort study (n = 1328) in the Republic of Seychelles, we examined the association between mode of delivery and 22 measures of child neurodevelopment spanning multiple domains: cognition, executive and psychomotor function, language development, behavior, scholastic achievement, and social communication. Using multivariable linear regression, we evaluated the relationship between delivery mode (Cesarean/vaginal delivery) and each developmental outcome, while controlling for relevant covariates including child sex and age, maternal age, maternal IQ, whether both parents lived with the child, and Hollingshead socioeconomic status.

RESULTS

At 20 months, children born via cesarean delivery had slightly higher scores (β = 0.11, 95% confidence interval: 0.00, 0.21) on the Infant Behavior Questionnaire-Revised Positive Affectivity/Surgency subtest, a measure of infant temperament, as compared to vaginal delivery. Delivery mode was not associated with any of the 7-year developmental outcomes.

CONCLUSIONS FOR PRACTICE

Our study does not support the notion that cesarean delivery is associated with child neurodevelopmental outcomes.

Early-life oxytocin attenuates the social deficits induced by caesarean-section delivery in the mouse

The oxytocin (OXT) system has been strongly implicated in the regulation of social behaviour and anxiety, potentially contributing to the aetiology of a wide range of neuropathologies. Birth by Caesarean-section (C-section) results in alterations in microbiota diversity in early-life, alterations in brain development and has recently been associated with long-term social and anxiety-like behaviour deficits. In this study, we assessed whether OXT intervention in the early postnatal period could reverse C-section-mediated effects on behaviour, and physiology in early life and adulthood. Following C-section or per vaginum birth, pups were administered with OXT (0.2 or 2 μg/20 μl; s.c.) or saline daily from postnatal days 1-5. We demonstrate that early postnatal OXT treatment has long-lasting effects reversing many of the effects of C-section on mouse behaviour and physiology. In early-life, high-dose OXT administration attenuated C-section-mediated maternal attachment impairments. In adulthood, low-dose OXT restored social memory deficits, some aspects of anxiety-like behaviour, and improved gastrointestinal transit. Furthermore, as a consequence of OXT intervention in early life, OXT plasma levels were increased in adulthood, and dysregulation of the immune response in C-section animals was attenuated by both doses of OXT treatment. These findings indicate that there is an early developmental window sensitive to manipulations of the OXT system that can prevent lifelong behavioural and physiological impairments associated with mode of birth.

Association between cesarean section and human capital in adulthood: 1982 and 1993 Pelotas birth cohorts, Rio Grande do Sul State, Brazil

This study aims to assess the association between mode of delivery and human capital among young adults enrolled in the 1982 and 1993 Pelotas birth cohorts, Rio Grande do Sul State, Brasil. In 1982 and 1993, the maternity hospitals of the municipality were daily visited, the births identified, and those live births, whose family lived in the urban area of Pelotas, were examined and their mothers interviewed. Information on mode of delivery, vaginal or cesarean, was provided by the mother in the perinatal study. Performance in intelligence tests achieved schooling and income were evaluated in the 30 years visit at the 1982 cohort. At the 1993 cohort, schooling and income were assessed at the 22 years visit, whereas IQ was evaluated at 18 years. Tobacco smoking in adulthood and type of school was used as negative outcomes to strength causal inference. Initially, cesarean section was positively associated with human capital at adulthood, with the exception of income in the 1993 cohort. After controlling for confounders, the magnitude of the associations was strongly reduced, and the regression coefficients were close to the null value. The negative outcome analysis showed that, after controlling for confounding variables, the mode of delivery was not associated with tobacco smoking and type of school. Suggesting that the variables included in the regression model to control for confounding, provided an adequate adjustment and it is unlikely that the results are due to residual confounding by socioeconomic status. On the other hand, considering the short- and long-term risks and the epidemic of cesarean sections, measures should be implemented to reduce its prevalence.

The association between birth weight and proxy-reported health-related quality of life among children aged 5 - 10 years old: A linked data analysis

Background

Birth weight has a substantial effect on children’s cognitive development, physical capability, and emotional development, which in turn impact on Health-Related Quality of Life (HRQoL). Generally, evidence indicates that children born with low birth weight tend to have poorer proxy-reported HRQoL, particularly at school age. However, there is limited evidence on whether variation in HRQoL exists across the entire range of possible birth weights. This study aimed to examine the association between birth weight and proxy-reported HRQoL among children aged 5–10 years old.

Methods

Data from the 1973–78 cohort of the Australian Longitudinal Study on Women’s Health were linked with state-based Perinatal Data Collections and the Mothers and their Children’s Health study for 1,589 mothers and 2,092 children aged 5 − 10 years old. Generalized estimating equations were used to model the association between birth weight and proxy-reported HRQoL measured by the Pediatric Quality of Life Inventory 4.0. Results are presented as odds ratios with 95 % confidence intervals.

Results

In this study, 15.61 % of children were at risk of impaired proxy-reported HRQoL. Each 100-gram increase in birth weight was associated with a 3 % reduction in the odds of impaired HRQoL (AOR = 0.97; 95 % CI: 0.94, 0.99). However, there was only limited evidence of an effect within the normal birth weight range (AOR = 0.97; 95 % CI: 0.94, 1.01).

Conclusions

The findings indicate that increased birth weight was protective against impaired HRQoL, although there was limited evidence of variability within the normal birth weight range. This study contributes to the existing literature by not only emphasizing the impact of low birth weight on children’s health and health-related outcomes but also by focusing on the variability within the normal birth weight range, particularly in a setting where low birth weight is less prevalent.

Maternal Mid-Gestation Cytokine Dysregulation in Mothers of Children with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a developmental disorder characterised by deficits in social interactions and communication, with stereotypical and repetitive behaviours. Recent evidence suggests that maternal immune dysregulation may predispose offspring to ASD. Independent samples t-tests revealed downregulation of IL-17A concentrations in cases, when compared to controls, at both 15 weeks (p = 0.02), and 20 weeks (p = 0.02), which persisted at 20 weeks following adjustment for confounding variables. This adds to the growing body of evidence that maternal immune regulation may play a role in foetal neurodevelopment.

The Influence of Cesarean Section on the Composition and Development of Gut Microbiota During the First 3 Months of Life

The intestinal microbiota has emerged as a critical regulator of growth and development in the early postnatal period of life. Cesarean section (CS) delivery is one of the strongest disrupting factors of the normal colonization process and has been reported as a risk factor for disorders in later life. In this study, we dynamically and longitudinally evaluated the impact of CS on the initial colonization pattern and development of gut microbiota by 16 healthy Chinese infants with fecal samples collected at 9 time points (day 5, day 8, day 11, week 2, week 4, week 6, week 7, month 2, and month 3) during the first 3 months of life. The V3–V4 regions of 16S rRNA gene were analyzed by Illumina sequencing. In comparison with vaginally delivered (VD) infants, infants born by CS showed decreased relative abundance of Bacteroides and Parabacteroides and enrichment of Clostridium_sensu_stricto_1, Enterococcus, Klebsiella, Clostridioides, and Veillonella. Most interestingly, Firmicutes/Bacteroidetes ratio was found to be significantly higher in the CS group than in the VD group from day 5 until month 3. Besides, the results of microbial functions showed that the VD group harbored significantly higher levels of functional genes in vitamin B6 metabolism at day 5, day 8, week 2, week 4, week 6, week 7, month 2, and month 3 and taurine and hypotaurine metabolism at day 5, while the phosphotransferase system and starch and sucrose metabolism involved functional genes were plentiful in the CS group at day 11, week 2, week 4, week 6, week 7, and month 2 and at week 2, week 7, and month 2, respectively. Our results establish a new evidence that CS affected the composition and development of gut microbiota in the first 3 months and provide a novel insight into strategies for CS-related disorders in later life.

The association between birth by caesarean section at term and offspring cognitive and academic performance: A birth cohort study

BACKGROUND

Caesarean section (CS) is associated with an increased risk of adverse health outcomes for both mothers and offspring. The evidence for an association between CS and reduced offspring cognitive and academic performance has been inconsistent, with considerable limitations.

AIM

The aim of this study is to compare cognitive and academic performance in childhood and early adulthood in offspring delivered by CS with those delivered vaginally at term.

MATERIALS AND METHODS

Data on 4327 mothers and offspring from a longitudinal birth cohort study were analysed. Offspring cognitive performance was measured by the Picture Peabody Vocabulary Test-Revised (PPVT-R) at ages five and 21 and the Raven's Standard Progressive Matrices at age 14. Academic achievement was assessed using the Wide Range Achievement Test at age 14.

RESULTS

After adjustment for confounding factors, there was no statistically significant association between cognitive performance and offspring birth mode at age five (P = 0.11). The adjusted difference of mean scores at five years on the PPVT-R for elective CS birth compared to those born by vaginal delivery was -2.2 (95% confidence interval (CI) -4.3 to -0.2), whereas for emergency CS it was 0.0 (95% CI -2.0 to 2.0). There were no differences in cognitive or academic performance at ages 14 and 21.

CONCLUSION

Birth mode was not significantly associated with offspring cognitive or academic performance. Our study does not support concerns that CS is associated with a reduction in cognitive performance.

Viral respiratory infections and psychosis: A review of the literature and the implications of COVID-19

The historical association between respiratory infections and neuropsychiatric symptoms dates back centuries, with more recent literature highlighting a link between viral infections and schizophrenia. Maternal influenza infection during pregnancy has been associated with the development of schizophrenia in offspring. Viral infections in neonates, children, and adolescents have also been associated with later development of schizophrenia. Neuroinvasive and/or systemic infections are thought to increase risk for psychopathology via inflammatory mechanisms, particularly when exposure occurs during critical neurodevelopmental windows. Several human coronaviruses (HCoVs) have been associated with psychotic disorders and increasing reports of the neuropsychiatric manifestations of COVID-19 suggest it has neuroinvasive properties similar to those of other HCoVs. These properties, in conjunction with its ability to generate a massive inflammatory response, suggest that COVID-19 may also contribute to future psychopathology. This review will summarize the psychopathogenic mechanisms of viral infections and discuss the neuroinvasive and inflammatory properties of COVID-19 that could contribute to the development of psychotic disorders, with a focus on in utero, neonatal, and childhood exposure.

Are there adverse outcomes for child health and development following caesarean section delivery? Can we justify using elective caesarean section to prevent obstetric pelvic floor damage?

INTRODUCTION AND HYPOTHESIS

Elective pre-labour Caesarean section (CS) delivery is widely regarded as the panacea for all pelvic floor dysfunction despite substantial epidemiological evidence that it is only partially protective. To demand a CS is also considered a right for the well-counselled patient, even without an elevated risk of incontinence or prolapse. In recent years there has been increasing data on possible adverse health outcomes for children delivered by CS over those delivered vaginally. This includes respiratory illness, atopic conditions, obesity, diabetes and other severe auto-immune diseases. Concern has also been raised over possible impacts on cognitive and neuropsychological development in these children. Often the response has been to dismiss these outcomes as a result of the indication for the CS birth such as antenatal compromise or maternal disease. However the marked increase in non-medical Caesarean delivery throughout many regions of the world has allowed us to better distinguish these contributing factors.

METHODS

This narrative review looks at some of the more recent evidence on adverse health and developmental outcomes associated with CS, particularly pre-labour CS and the implications for the long term health of our society.

RESULTS

Epidemiological studies and animal research indicate an increased risk of negative impacts on child physical health and neuro-cognitive development aftercaesarean section delivery, particularly pre-labour Caesarean section, compared with vaginal delivery. This elevated risk persists after correction forobstetric and maternal factors.

CONCLUSION

Caesarean section delivery can result in adverse outcomes for infant, maternal and societal wellbeing. Elective Caesarean section, purely to potentially minimise pelvic floor dysfunction, cannot be justified.

The association of birth by caesarean section and cognitive outcomes in offspring: a systematic review

PURPOSE

Studies have reported children born by caesarean section are more likely to have lower cognitive outcomes compared to those born by vaginal delivery. This paper reviews the literature examining caesarean birth and offspring cognitive outcomes.

METHODS

A systematic search for observational studies or case-control studies that compared cognitive outcomes of people born by caesarean section with those born by vaginal delivery was conducted in six databases (Medline, PubMed, EMBASE, PsychInfo, CINAHL, Web of Science) from inception until December 2019 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were assessed for quality and a narrative synthesis was undertaken considering the evidence for a causal relationship according to the Bradford Hill Criteria.

RESULTS

A total of seven studies were identified. Of these, four found a significant association between elective and emergency caesarean birth and reduction in offspring cognitive performance as measured by school performance or validated cognitive testing. Three studies found no association. There was variability in the quality of the studies, assessment of the reason for caesarean section (emergency vs elective), measurement of outcomes and adjustment for confounding factors.

CONCLUSION

The evidence of an association between CS birth and lower offspring cognitive functioning is inconsistent. Based on currently available data, there is no evidence that a causal association exists. To better examine this association, future studies should (a) distinguish elective and emergency caesareans, (b) adequately adjust for confounding variables and (c) have valid outcome measures of cognition.

Anesthesia, sex and miscarriage history may influence the association between cesarean delivery and autism spectrum disorder

BACKGROUND

To explore the association between cesarean section (CS) and risk of autism spectrum disorder (ASD), and evaluate the possible factors influencing this association.

METHODS

In total, 950 patients diagnosed with ASD and 764 healthy controls were recruited in this study. Socio-demographic characteristics and prenatal, perinatal, and neonatal characteristics were compared between the two groups. Univariate and multivariable conditional logistic regression analyses were applied to adjust for confounders. Further stratified analyses based on sex and miscarriage history were similarly performed to explore the factors influencing the association between CS and ASD.

RESULTS

CS was evidently associated with an elevated risk of ASD (adjusted odds ratio [aOR] = 1.606, 95% confidence interval (CI) = 1.311-1.969). Unlike regional anesthesia (RA), only CS performed under general anesthesia (GA) consistently elevated the risk of ASD (aOR = 1.887, 95% CI = 1.273-2.798) in females and males in further stratified analysis. The risk of children suffering from ASD following emergency CS was apparently increased in males (aOR = 2.390, 95% CI = 1.392-5.207), whereas a higher risk of ASD was observed among voluntary CS and indicated CS subgroups (aOR = 2.167, 95% CI = 1.094-4.291; aOR = 2.919, 95% CI = 1.789-4.765, respectively) in females. Moreover, the interaction term of CS and past miscarriage history (β = - 0.68, Wald χ2 = 7.5, df = 1, p = 0.006)) was similarly defined as influencing ASD.

CONCLUSIONS

The exposure of children to GA during CS may explain the possible/emerging association between CS and ASD. In addition, sex and miscarriage history could equally be factors influencing the association between CS and ASD.

Birth signalling hormones and the developmental consequences of caesarean delivery

Rates of delivery by caesarean section (CS) are increasing around the globe and, although several epidemiological associations have already been observed between CS and health outcomes in later life, more are sure to be discovered as this practice continues to gain popularity. The components of vaginal delivery that protect offspring from the negative consequences of CS delivery in later life are currently unknown, although much attention to date has focused on differences in microbial colonisation. Here, we present the case that differing hormonal experiences at birth may also contribute to the neurodevelopmental consequences of CS delivery. Levels of each of the 'birth signalling hormones' (oxytocin, arginine vasopressin, epinephrine, norepinephrine and the glucocorticoids) are lower following CS compared to vaginal delivery, and there is substantial evidence for each that manipulations in early life results in long-term neurodevelopmental consequences. We draw from the research traditions of neuroendocrinology and developmental psychobiology to suggest that the perinatal period is a sensitive period, during which hormones achieve organisational effects. Furthermore, there is much to be learned from research on developmental programming by early-life stress that may inform research on CS, as a result of shared neuroendocrine mechanisms at work. We compare and contrast the effects of early-life stress with those of CS delivery and propose new avenues of research based on the links between the two bodies of literature. The research conducted to date suggests that the differences in hormone signalling seen in CS neonates may produce long-term neurodevelopmental consequences.

Associations Between Mode of Birth and Neuropsychological Development in Children Aged 4 Years: Results from a Birth Cohort Study

The aim of this prospective longitudinal study was to examine the association between Cesarean section (CS) and child development and behavior. The sample consisted of 256 children who were born at term without serious perinatal pathologies. Their development and behavior was assessed at the age of four using Ages and Stages Questionnaire (ASQ-3), Children's Behavior Questionnaire and Strength and Difficulties Questionnaire. Multivariate linear regression analyses were conducted to assess the association between CS and child outcomes. CS was associated with better scores in the Problem Solving domain of the ASQ in the whole sample. After stratifying by child sex, the positive association between CS and the Problem Solving domain was significant in boys, while no association was found in girls. Girls were rated less optimally in the Gross Motor domain of the ASQ when born via CS. Mode of birth was not associated with behavioral outcomes.

Effects of delivery mode on behavior in mouse offspring

Cesarean section (CS) has been associated with an increased risk of mental disorders in the offspring. This could possibly be explained by an inadequate microbial colonization early in life with a consequential disturbed gut-brain interaction. To investigate the link between delivery mode and behavior and develop a suitable animal model for further research of the gut-brain axis, the aim of this study was to characterize the gut microbiota (GM) together with the behavioral response in various behavioral tests in CS-delivered mice. We hypothesized that mice delivered by CS would present with disturbances in normal physiological behavior possibly due to an inadequate microbial colonization. C57BL/6 mice delivered by CS or vaginal delivery (VD) were cross fostered and, as adults, observed for anxiety-related behavior in the open field test, social deficits in a sociability test and compulsive behavior in the marble burying test. GM was analyzed by 16S rRNA gene amplicon sequencing. The open field test showed that CS-delivered mice had a decreased activity and accelerated defecation compared to VD-delivered mice. In addition, CS-delivered female mice spend less time interacting with cage mates in the sociability test, whereas there was no effect of CS delivery on the average number of marbles buried. In conclusion, CS-delivered mice had a more pronounced anxiety-like behavior and showed less preference for sociability in female offspring.

Birth by caesarean section and educational achievement in adolescents

BACKGROUND

Birth by caesarean section has been shown to alter the composition of the early infant gut microbiota and postulated to influence cognitive outcomes via the gut-brain axis.

AIMS

To determine whether birth by caesarean section is associated with secondary school educational achievement.

METHODS

Whole-population administrative data were used from anonymised individual level linkage of birth records to educational and health information from the New Zealand Integrated Data Infrastructure (IDI). Participants were 111 843 children born between 1 January 1996 and 31 December 1998 for whom mode of delivery information was available from International Classification of Diseases 9th edition codes in maternal records. The National Certificate of Educational Achievement (NCEA) is the main secondary school qualification undertaken by New Zealand students. Multivariable linear regression models were used to examine the association between mode of delivery and educational achievement. A family fixed effect analysis compared educational achievement outcomes in sibling pairs where one sibling was delivered by caesarean section and one delivered vaginally.

RESULTS

After adjustment for potential confounders, there was no significant association between mode of delivery and achievement of university entrance (odds ratio = 0.98, 95% CI: 0.94-1.02). NCEA percentile scores were lower in caesarean born infants (Estimate = -0.37, 95% CI: -0.69 to -0.06)). However, in the fixed effect sibling analysis caesarean section was no longer significantly associated with NCEA percentile scores.

CONCLUSIONS

We find that caesarean section is not related to educational outcomes, suggesting that even if the infant gut microbiota is altered in caesarean section, it does not appear to have a measurable impact on adolescent academic achievement.

Elective Caesarean Delivery Associated with Infant Hospitalisation for Intestinal But Not Respiratory Infection

OBJECTIVES

We assessed the impact of caesarean delivery on offspring respiratory and intestinal infection.

METHODS

Data were extracted from all live births (n = 429,058) occurring in the Australian state of Queensland between January 2009 and December 2015, and followed for 12 months. Births were categorised as either non-medically indicated caesarean or vaginal delivery and each offspring had a record (present/absent) of respiratory and intestinal infection hospitalisation for each month from birth to 12 months.

RESULTS

Infants delivered by non-medically indicated caesarean were more likely to experience respiratory infection [OR = 1.51 (1.15, 1.99)] and intestinal infection [OR = 1.74 (1.19, 2.55)] than those born by vaginal delivery. In the propensity score weighted analyses the estimate for respiratory infection was similar but non-significant [OR = 1.52 (0.99, 2.31)], while the association with intestinal infection strengthened [OR = 2.21 (1.25, 3.89)].

CONCLUSIONS FOR PRATICE

Our findings provide strong evidence for a specific and clinically meaningful link between non-medically indicated caesarean delivery and infant intestinal infection.

The Impact of Cesarean and Vaginal Delivery on Results of Psychological Cognitive Test in 5 Year Old Children

Background and objectives: The impact of cesarean and vaginal delivery on cognitive development was analyzed in 5 year old children. Materials and Methods: Two cohorts of 5 year old children born in the years 2013 and 2014 in Karvina (Northern Moravia) and Ceske Budejovice (Southern Bohemia) were studied for their cognitive development related to vaginal (n = 117) and cesarean types of delivery (n = 51). The Bender Visual Motor Gestalt Test (BG test) and the Raven Colored Progressive Matrices (RCPM test) were used as psychological tests. Results: In the comparison of vaginal delivery vs. cesarean section, the children delivered by cesarean section scored lower and, therefore, achieved poorer performance in cognitive tests compared to those born by vaginal delivery, as shown in the RCPM (p < 0.001) and in the BG test (p < 0.001). When mothers' education level was considered, the children whose mothers achieved a university degree scored higher in both the RCPM test (p < 0.001) and the BG test (p < 0.01) compared to the children of mothers with lower secondary education. When comparing mothers with a university degree to those with higher secondary education, there was a significant correlation between level of education and score achieved in the RCPM test (p < 0.001), but not in the BG test. Conclusions: According to our findings, the mode of delivery seems to have a significant influence on performance in psychological cognitive tests in 5 year old children in favor of those who were born by vaginal delivery. Since cesarean-born children scored notably below vaginally born children, it appears possible that cesarean delivery may have a convincingly adverse effect on children's further cognitive development.

Delivery mode-associated gut microbiota in the first 3 months of life in a country with high obesity rates: A descriptive study

Delivery methods during childbirth and their related gut microbiota profiles have important impacts on health later in life, they can contribute to the development of diseases such as obesity, whose highest prevalence rate is found among the Mexican child population. Coincidentally, Mexico has one of the highest global average annual rate increase in cesarean births (C-section). Since Mexico leads the world in childhood obesity, studying the relationship between childbirth delivery methods and gut microbiota profiles in this vulnerable population may be used to identify early risk factors for obesity in other developed and developing countries. The objective of this study is to determine the association between child delivery method and gut microbiota profiles in healthy Mexican newborns.Fecal samples of 57 term infants who participated in a randomized clinical trial in 2013 to study the safety of Agave fructans in newborns, were used in this study. DNA samples were extracted and used to characterize the microbiota composition using high-throughput 16S rRNA gene sequencing. The samples were further divided based on childbirth delivery method, as well as early diet. Gut microbiota profiles were determined and analyzed using cluster analysis followed by multiple correspondence analysis.An unusual high abundance of Proteobacteria was found in the gut microbiota of all Mexican infants studied, regardless of delivery method. Feces from infants born by C-section had low levels of Bacteroidetes, high levels of Firmicutes, especially Clostridium and Enterococcus, and a strikingly high ratio of Firmicutes/Bacteroidetes (F:B). Profiles enriched in Bacteroidetes and low F:B ratios, were strongly associated with vaginal delivery.The profile of gut microbiota associated with feces from Mexican infants born by C-section, may be added to the list of boosting factors for the worrying obesity epidemic in Mexico.

Prelabour caesarean section and neurodevelopmental outcome at 4 and 12 months of age: an observational study

Background

With prelabour caesarean section rates growing globally, there is direct and indirect evidence of negative cognitive outcomes in childhood. The objective of this study was to assess the short-term neurodevelopmental outcomes after prelabour caesarean section as compared to vaginally born infants.

Methods

We conducted a prospective, observational study of infants delivered by prelabour caesarean section at the Hospital of Halland, Halmstad, Sweden and compared their development with an historical group of infants born by non-instrumental vaginal delivery.

Results

Infants born by prelabour caesarean section were compared with a group of vaginally born infants. Follow-up assessments were performed at 4 and 12 months. Prelabour caesarean infants (n = 66) had significantly lower Ages and Stages Questionnaire, second edition (ASQ-II) scores in all domains (communication, gross motor, fine motor, problem solving and personal-social) at 4 months of age with an adjusted mean difference (95% CI) of − 20.7 (− 28.7 to − 12.6) in ASQ-II total score as compared to vaginally born infants (n = 352). These differences remained for gross-motor skills at the 12 month assessment, adjusted mean difference (95% CI) -4.7 (− 8.8 to − 0.7), n = 62 and 336.

Conclusions

Adverse neurodevelopmental outcomes in infants born by prelabour caesarean section may be apparent already a few months after birth. Additional studies are warranted to explore this relationship further.

The AEDUCATE Collaboration. Comprehensive antenatal education birth preparation programmes to reduce the rates of caesarean section in nulliparous women. Protocol for an individual participant data prospective meta-analysis

INTRODUCTION

Rates of medical interventions in normal labour and birth are increasing. This prospective meta-analysis (PMA) proposes to assess whether the addition of a comprehensive multicomponent birth preparation programme reduces caesarean section (CS) in nulliparous women compared with standard hospital care. Additionally, do participant characteristics, intervention components or hospital characteristics modify the effectiveness of the programme? METHODS AND ANALYSIS: Population: women with singleton vertex pregnancies, no planned caesarean section (CS) or epidural.Intervention: in addition to hospital-based standard care, a comprehensive antenatal education programme that includes multiple components for birth preparation, addressing the three objectives: preparing women and their birth partner/support person for childbirth through education on physiological/hormonal birth (knowledge and understanding); building women's confidence through psychological preparation (positive mindset) and support their ability to birth without pain relief using evidence-based tools (tools and techniques). The intervention could occur in a hospital-based or community setting.Comparator: standard care alone in hospital-based maternity units.

OUTCOMES

Primary: CS.Secondary: epidural analgesia, mode of birth, perineal trauma, postpartum haemorrhage, newborn resuscitation, psychosocial well-being.Subgroup analysis: parity, model of care, maternal risk status, maternal education, maternal socio-economic status, intervention components.

STUDY DESIGN

An individual participant data (IPD) prospective meta-analysis (PMA) of randomised controlled trials, including cluster design. Each trial is conducted independently but share core protocol elements to contribute data to the PMA. Participating trials are deemed eligible for the PMA if their results are not yet known outside their Data Monitoring Committees.

ETHICS AND DISSEMINATION

Participants in the individual trials will consent to participation, with respective trials receiving ethical approval by their local Human Research Ethics Committees. Individual datasets remain the property of trialists, and can be published prior to the publication of final PMA results. The overall data for meta-analysis will be held, analysed and published by the collaborative group, led by the Cochrane PMA group.

TRIAL REGISTRATION NUMBER

CRD42020103857.

The association between caesarean section and cognitive ability in childhood

PURPOSE

Global rates of caesarean section (CS) rates have increased rapidly in recent years. This is a growing public health concern as it has been proposed that CS may impact cognitive outcomes in childhood. However, the evidence for this association is limited and inconsistent. Therefore, the aim of this study was to investigate the relationship between obstetric mode of delivery and longitudinal cognitive outcomes in childhood.

METHODS

We examined this question using data from a longitudinal cohort study of 8845 participants from the Millennium Cohort Study, a nationally representative UK cohort, who completed a range of verbal and visual-spatial cognitive assessments at ages 3, 5, 7 and 11 years.

RESULTS

We found a statistically significant association between planned CS and visual-spatial cognitive delay in the pattern construction assessment at age 5 (OR 1.31, 95% CI 0.99-1.72) and age 7 (OR 1.42, 95% CI 1.12-1.81). Additionally planned CS was also associated with increased odds of "early childhood delay" (OR 1.70, 95% CI 1.15-2.50) and borderline increased odds of "persistent delay" (OR 1.37, 95% CI 0.99-1.89) in visual-spatial cognitive tests. Mode of delivery was not associated with verbal ability or with patterns of delay at any age point in verbal cognitive tests.

CONCLUSION

We have reported a small association between planned CS and visual-spatial cognitive delay in childhood. However, while this result should be interpreted with caution, it highlights the need to further explore this potential relationship and the causal basis of such an association.