Association of Elective and Emergency Cesarean Delivery With Early Childhood Overweight at 12 Months of Age

The association between caesarean section delivery and obesity at age 17 years. Evidence from a longitudinal cohort study in the United Kingdom

BACKGROUND

Childhood and adolescent obesity are major, preventable public health concerns. Studies to date are inconclusive regarding an association between caesarean section (CS) delivery and offspring obesity, with fewer studies conducted in late adolescence. This study examined the association between CS delivery, with a specific focus on planned CS, and induction of labour and adolescent body mass index (BMI) and body fat percentage (BF%) at age 17 years.

METHODS

Data on 8,880 mother-child pairs from the United Kingdom Millennium Cohort Study were analysed. The exposures were mode of delivery (normal vaginal delivery (VD) (reference), assisted VD, planned CS and emergency CS) and mode of delivery by induction of labour status. Crude and adjusted binary logistic regression and linear regression models were fitted examining BMI and BF% at age 17 years respectively, adjusting for several potential confounders.

RESULTS

Adolescents born by CS did not have an elevated BMI or BF% compared to those born by normal VD. The fully adjusted results for overweight and obesity in children born by planned CS, compared to VD, were 1.05 (95% CI: 0.86-1.28) and 0.94 (95% CI: 0.72-1.23), respectively. The results were similar for the associations between CS and BF%, and between induction of labour and BMI.

CONCLUSION

Overall, this large longitudinal study did not support an association between CS or induction of labour and overweight, obesity or BF%. It is possible that previously reported associations are due to residual or unmeasured confounding and/or underlying indications for CS delivery.

Pre-labor and post-labor cesarean delivery and early childhood adiposity in the Canadian Healthy Infant Longitudinal Development (CHILD) Cohort Study

BACKGROUND/OBJECTIVES

Delivery by cesarean section (CS) compared to vaginal delivery has been associated with increased risk of overweight in childhood. Our study examined if the presence or absence of labor events in CS delivery altered risk of overweight in early childhood (1-5 years) compared to vaginal delivery and if this association differed according to infant sex.

SUBJECTS/METHODS

The study included 3073 mother-infant pairs from the CHILD Cohort Study in Canada. Data from birth records were used to categorize infants as having been vaginally delivered, or delivered by CS, with or without labor events. Age and sex adjusted weight-for-length (WFL) and body mass index (BMI) z scores were calculated from height and weight data from clinic visits at 1, 3 and 5 years and used to classify children as overweight. Associations between delivery mode and child overweight at each timepoint were assessed using regression models, adjusting for relevant confounding factors including maternal pre-pregnancy BMI. Effect modification by infant sex was tested.

RESULTS

One in four infants (24.6%) were born by CS delivery; 13.0% involved labor events and 11.6% did not. Infants born by CS without labor had an increased odds of being overweight at age 1 year compared to vaginally delivered infants after adjustment for maternal pre-pregnancy BMI, maternal diabetes, smoking, infant sex and birthweight-for-gestational age (aOR 1.68 [95% CI 1.05-2.67]). These effects did not persist to 3 or 5 years of age and, after stratification by sex, were only seen in boys (aOR at 1 year 2.21 [95% CI 1.26-3.88]).

CONCLUSION AND RELEVANCE

Our findings add to the body of evidence that CS, in particular CS without labor events, may be a risk factor for overweight in early life, and that this association may be sex-specific. These findings could help to identify children at higher risk for developing obesity.

Changes in anthropometry in full-term breastfed newborns and associated factors for the first month

OBJECTIVE

We aim to assess the changes and associated factors in newborn anthropometry in the first month for full-term, healthy, and exclusive-breastfed infants.

METHODS

Neonatal anthropometric measurements were taken on day 5, day 15, and day 30 after delivery. Generalized estimating equations (GEE) analyzed the changes.

RESULTS

From 169 mother-newborn pairs, GEE showed that weight gain during the first month was influenced by maternal body mass index (BMI), delivery type, birth weight, and jaundice after adjusting confounding factors (p < .05). The neonatal length was affected by the smoking status of parents, gestational maternal health problems, maternal height, birth weight, and jaundice (p < .05). Neonatal head circumference was influenced by the smoking status of parents, gestational maternal health problems, maternal BMI, delivery type, maternal height, and birth weight.

CONCLUSION

Adverse perinatal factors including mother's smoke exposure, maternal obesity and diabetes, cesarean birth, and neonatal hyperbilirubinemia influence anthropometry in the first months of life.

Delivery by cesarean section leads to heavier adult bodyweight in prairie voles (Microtus ochrogaster)

Delivery by cesarean section now makes up 32.1 % of all births in the United States. Meta-analyses have estimated that delivery by cesarean section is associated with a > 50 % increased risk for childhood obesity by 5 years of age. While this association is independent of maternal obesity, breastfeeding, and heritable factors, studies in humans have been unable to test for a causal role of cesarean delivery in this regard. Here, we set out to use an animal model to experimentally test whether delivery by cesarean section would increase offspring weight in adulthood. Delivery by cesarean section may exert neurodevelopmental consequences by impacting hormones that are important at birth as well as during metabolic regulation in later life, such as oxytocin and vasopressin. The prairie vole (Microtus ochrogaster) has long been studied to investigate the roles of oxytocin and vasopressin in brain development and social behavior. Here, we establish that prairie voles tolerate a range of ambient temperatures, including conventional 22° housing, which makes them translationally appropriate for studies of diet-induced obesity. We also studied vole offspring for their growth, sucrose preference, home cage locomotor activity, and food consumption after birth by either cesarean section or vaginal delivery. At sacrifice, we collected measures of weight, length, and adipose tissue to analyze body composition in adulthood. Voles delivered by cesarean section had consistently greater bodyweights than those born vaginally, despite having lower food consumption and greater locomotive activity. Cesarean-delivered animals were also longer, though this did not explain their greater body weights. While cesarean delivery had no effect on vasopressin, it resulted in less oxytocin immunoreactivity within the hypothalamus in adulthood. These results support the case that cesarean section delivery plays a causal role in increasing offspring body weight, potentially by affecting the oxytocin system.

Evaluating the association between caesarean delivery and weight status in early childhood in a Japanese birth cohort study

To examine whether the prevailing hypothesis of an association between caesarean section (CS) delivery method and increased weight status in early childhood is observed in Japanese. A total of 1277 mother-infant pairs from a prospective hospital-based mother-infant birth cohort that recruited women in their first trimester from May 2010 to November 2013 were included. We assessed the relationship between delivery method and weight status of delivered children at 1, 3 and 6 years of age. In total, 366 children (28.7%) were delivered by CS. Delivery by CS was not associated with body mass index (BMI) z-score (≥ 75 percentile) at age 1 year, (odds ratio (OR) 0.97, 95% confidence interval (CI) 0.69-1.36), 3 years (OR 0.98, 95% CI 0.67-1.42), and 6 years (OR 0.71, 95% CI 0.45-1.12), and also showed no association with low weight status (< 25th percentile). Supplemental evaluations addressing the influence of preterm births, pre-pregnancy BMI, emergency CS, and modification by breastfeeding were consistent with the primary analyses. Our findings do not support the hypothesis that children born by CS are at risk of being overweight in childhood among the Japanese population.

Ultra-Processed Food as Mediator of the Association between Birthweight and Childhood Body Weight Outcomes: A Retrospective Cohort Study

Previous studies have shown conflicting findings regarding the association between birthweight and childhood adiposity. We aimed to explore the interaction between ultra-processed food (UPF) and birthweight and its associations with bodyweight markers. The retrospective analysis of data from a Multicity Cohort Study across eastern China was conducted. UPF was computed as percentage of the energy intake and categorized into quartiles. Birthweight was categorized into low (LBW), normal (NBW) and high (HBW). The BMI z-score was calculated using the lambda-mu-sigma method. The sex- and age-specific BMI cutoff points were used to define weight status. Generalized linear models were used to examine modification effects and were performed after adjustment for covariates. The mean percentage of energy intake from UPF was 27.7% among 1370 children. Of all children, 2.3% and 21.4% were born with LBW and HBW, respectively. HBW was a permanent risk for high BMI measures, while LBW was associated with increased BMI measurements only by the addition of the interaction term. The subgroup analysis revealed that HBW and LBW were positively associated with BMI measurements in the lowest UPF intake (Q1), while HBW was related to high BMI measures in Q4. Our findings support efforts to recommend limiting UPF intake, especially for LBW children.

Lasting consequences on physiology and social behavior following cesarean delivery in prairie voles

Cesarean delivery is associated with diminished plasma levels of several 'birth-signaling' hormones, such as oxytocin and vasopressin. These same hormones have been previously shown to exert organizational effects when acting in early life. For example, our previous work found a broadly gregarious phenotype in prairie voles exposed to oxytocin at birth. Meanwhile, cesarean delivery has been previously associated with changes in social behavior and metabolic processes related to oxytocin and vasopressin. In the present study, we investigated the long-term neurodevelopmental consequences of cesarean delivery in prairie voles. After cross-fostering, vole pups delivered either via cesarean or vaginal delivery were studied throughout development. Cesarean-delivered pups responded to isolation differently in terms of their vocalizations (albeit in opposite directions in the two experiments), huddled in less cohesive groups under warmed conditions, and shed less heat. As young adults, we observed no differences in anxiety-like or alloparental behavior. However, in adulthood, cesarean-delivered voles of both sexes failed to form partner preferences with opposite sex conspecifics. In a follow-up study, we replicated this deficit in partner-preference formation among cesarean-delivered voles and were able to normalize pair-bonding behavior by treating cesarean-delivered vole pups with oxytocin (0.25 mg/kg) at delivery. Finally, we detected minor differences in regional oxytocin receptor expression within the brains of cesarean-delivered voles, as well as microbial composition of the gut. Gene expression changes in the gut epithelium indicated that cesarean-delivered male voles have altered gut development. These results speak to the possibility of unintended developmental consequences of cesarean delivery, which currently accounts for 32.9 % of deliveries in the U.S. and suggest that further research should be directed at whether hormone replacement at delivery influences behavioral outcomes in later life.

Caesarean Section Delivery Is Associated with Childhood Overweight and Obesity, Low Childbirth Weight and Postnatal Complications: A Cross-Sectional Study

Background and Objectives: In the last decades, simultaneously increasing trends have been recorded for both caesarean section delivery and childhood overweight/obesity around the world, which are considered serious public health concerns, negatively affecting child health. Aim: The present study aims to investigate whether caesarean section is associated with the increased rates of childhood overweight/obesity, low childbirth anthropometric indices and postnatal complications in pre-school age. Materials and Methods: This is a cross-sectional study in which 5215 pre-school children aged 2–5 years old were enrolled from nine different Greek regions after applying specific inclusion and exclusion criteria. Non-adjusted and adjusted statistical analysis was performed to assess the impact of caesarean section in comparison to vaginal delivery. Results: Children delivered by caesarean section were significantly more frequently overweight or obese at the age of 2–5 years, also presenting a higher prevalence of low birth weight, length and head circumference. Caesarean section was also associated with higher incidence of asthma and diabetes type I at the age of 2–5 years. In a multivariate analysis, caesarean section increased the risk of childhood overweight/obesity and low childbirth anthropometric indices even if adjusting for several childhood and maternal confounding factors. Conclusions: Increasing trends were recorded for both caesarean section delivery and childhood overweight/obesity, which are considered serious public health concerns. Caesarean section independently increased childhood overweight/obesity in pre-school age, highlighting the emergent need to promote health policies and strategies to inform future mothers about its short and long-term risks and that this mode of delivery should preferably be performed only when there are strong medical recommendations in emergency obstetric conditions.

Estimating the effect of cesarean delivery on long-term childhood health across two countries

Assessing the impact of cesarean delivery (CD) on long-term childhood outcomes is challenging as conducting a randomized controlled trial is rarely feasible and inferring it from observational data may be confounded. Utilizing data from electronic health records of 737,904 births, we defined and emulated a target trial to estimate the effect of CD on predefined long-term pediatric outcomes. Causal effects were estimated using pooled logistic regression and standardized survival curves, leveraging data breadth to account for potential confounders. Diverse sensitivity analyses were performed including replication of results in an external validation set from the UK including 625,044 births. Children born in CD had an increased risk to develop asthma (10-year risk differences (95% CI) 0.64% (0.31, 0.98)), an average treatment effect of 0.10 (0.07-0.12) on body mass index (BMI) z-scores at age 5 years old and 0.92 (0.68-1.14) on the number of respiratory infection events until 5 years of age. A positive 10-year risk difference was also observed for atopy (10-year risk differences (95% CI) 0.74% (-0.06, 1.52)) and allergy 0.47% (-0.32, 1.28)). Increased risk for these outcomes was also observed in the UK cohort. Our findings add to a growing body of evidence on the long-term effects of CD on pediatric morbidity, may assist in the decision to perform CD when not medically indicated and paves the way to future research on the mechanisms underlying these effects and intervention strategies targeting them.

Sex-specific association between elective cesarean section and growth trajectories in preschool children: A prospective birth cohort study

Background

Elective cesarean section (ECS) primarily contributes to the rising cesarean section (CS) rate, and much attention has been attracted to its health consequences. The association between ECS and overweight and obesity in children has been controversial, and few studies distinguished ECS with medical indications from those without indications. Based on a large sample birth cohort, we aim to examine the association of ECS with or without medical indications on children's physical development by using repeated anthropometric data from birth to 6 years of age.

Methods

A total of 2304 mother-child pairs with complete data on delivery mode and children's anthropometric measurements were recruited from the Ma'anshan-Anhui Birth Cohort (MABC) in China. ECS was the main exposure in this study, and the primary outcomes were children's growth trajectories and early adiposity rebound (AR). Children's BMI trajectories were fitted by using group-based trajectory models and fractional polynomial mixed-effects models. The association between ECS and children's growth trajectories and early AR was performed using multiple logistic regression models.

Results

Among 2,304 mother-child pairs (1199 boys and 1105 girls), 1088 (47.2%) children were born by CS, including 61 (5.6%) emergency CS, 441 (40.5%) ECS with medical indications, and 586 (53.9%) ECS without medical indications. After adjusting for potential confounders, it was found that ECS with medical indications was associated with a "high level" of BMI trajectory (OR = 1.776; 95% CI: 1.010-3.123), and ECS without medical indications was associated with early AR (OR = 1.517; 95% CI: 1.123-2.050) in girls. In boys, we found that ECS without medical indications was unlikely to experience an accelerated growth trajectory (OR = 0.484; 95%CI: 0.244-0.959).

Conclusions

ECS may be related to girls' "high level" BMI trajectories and early AR. If causal, the findings will provide an evidence-based reference for early life interventions for childhood obesity.

Fetal congenital heart disease - mode of delivery and obstetrical complications

Background

The optimal mode of delivery in cases of fetal congenital heart disease (CHD) is not established. The few relevant studies did not address operative vaginal delivery. The aim of this study was to assess the impact of fetal CHD on mode of delivery during a trial of labor, and to secondarily describe some obstetric complications.

Methods

The database of a tertiary medical center was searched for women who gave birth to a singleton, liveborn neonate in 2015–2018. Mode of delivery was compared between women carrying a fetus with known CHD and women with a healthy fetus matched 1:5 for maternal age, parity, body mass index, and gestational age.

Results

The cohort included 616 women, 105 in the CHD group and 511 in the control group. The rate of operative vaginal delivery was significantly higher in the CHD group (18.09% vs 9.78%, OR 2.03, 95% CI 1.13–3.63, p = 0.01); the difference remained significant after adjustment for nulliparity and gestational age at delivery (aOR 2.58, 95% CI 1.36–4.9, p < 0.01). There was no difference between the CHD and control group in rate of intrapartum cesarean delivery (9.52% vs 10.76%, respectively, OR 0.97, 95% CI 0.47–1.98, p = 0.93). The most common indication for operative vaginal delivery was non-reassuring fetal heart rate (78.94% vs 64%, respectively). Median birth weight percentile was significantly lower in the CHD group (45th vs 53rd percentile, p = 0.04).

Conclusions

Our findings suggest that operative vaginal delivery, performed mostly because of non-reassuring fetal heart rate, is more common in pregnancies complicated by a prenatal diagnosis of CHD than non-anomalous pregnancies.

Relationship between caesarean section delivery and risk of overweight/obesity among children aged 6–23 months in the Tamale Metropolis of Ghana

The recent exponential increase in caesarean section (CS) rates in many countries including Ghana requires an understanding of the potential long-term consequences on child health. The present study investigated the relationship between CS delivery and risk of childhood overweight/obesity. A retrospective cohort study was conducted from October 2019 to March 2020 in Ghana. Using multi-stage sampling, 553 mother–child pairs aged 6–23 months were selected from ten health facilities during child welfare clinic (CWC) services. We assessed the association between delivery mode (caesarean v. vaginal) and subsequent body mass index for age (BMI/age Z-score) using hierarchical multivariable linear regression analysis. The prevalence of overweight/obesity (BMI/age Z-score > +2 sd) in children was 3⋅6 %. After adjusting for maternal gestational weight gain, macrosomia and child feeding practices, children who were born through CS had mean BAZ which was 0⋅105 standard units significantly higher than their colleagues who were delivered through normal vaginal [beta coefficient (β) 0⋅105, (95 % CI 0⋅03, 0⋅55)]. CS birth was also associated with 3⋅2 times higher odds of overweight/obesity than vaginal delivery (AOR 3⋅23; 95 % CI 1⋅14, 9⋅13). Consequently, CS delivery was associated positively with increased body mass (adiposity) in the study sample. The association between CS delivery and risk of childhood obesity was attenuated after adjusting for macrosomia. These results would be important for informing clinicians and expectant mothers in considering CS delivery.

Does the gut microbiome mediate antipsychotic-induced metabolic side effects in schizophrenia?

INTRODUCTION

Second-generation antipsychotics (SGAs) are the most effective treatment for people with schizophrenia. Despite their effectiveness in treating psychotic symptoms, they have been linked to metabolic, cardiovascular and gastrointestinal side-effects. The gut microbiome has been implicated in potentiating symptoms of schizophrenia, response to treatment and medication-induced side effects and thus presents a novel target mediating second-generation antipsychotic-induced side effects in patients.

AREAS COVERED

This narrative review presents evidence from clinical and pre-clinical studies exploring the relationship between the gut microbiome, schizophrenia, second-generation antipsychotics and antipsychotic-induced side-effects. It also covers evidence for psychobiotic treatment as a potential supplementary therapy for people with schizophrenia.

EXPERT OPINION

The gut microbiome has the potential to mediate antipsychotic-induced side-effects in people with schizophrenia. Microbiome-focused treatments should be considered in combination with standard therapy in order to ameliorate debilitating drug-induced side effects, increase quality of life and potentially improve psychotic symptoms. Future studies should aim to collect not only microbiome data, but also metabolomic measures, dietary information and behavioral data.

Cesarean Delivery and Risk of Excess Weight Among Brazilian Preschool Children

OBJECTIVE

To study the relationship between cesarean Delivery (CD) and overweight in preschool children, considering the presence of birth aspects and demographic characteristics that have been associated with the risk of excess weight.

METHODS

This retrospective cross-sectional analysis used representative data of children from 2 to 6 years of age at municipal daycare centers in Taubaté, São Paulo, Brazil. The sample included 752 preschoolers. Weight and height were collected in daycare centers, and the nutritional status classification was performed using z scores of Body Mass Index (zBMI). Data analysis was performed in the bivariate and multivariate manner, the latter with the inclusion of another possible risk factor. Adjustments were made for daycare centers time, sex, birth length and weight and maternal schooling.

RESULTS

The mean age of preschool children was 4.7 years, and 53.8% were boys. The prevalence of overweight children was 21.7%. The median zBMI of the children born by CD was higher than that of vaginal Delivery (p = 0.0194). The prevalence of overweight showed association with CD (p = 0.0196; PR = 1.397 with 95% CI of 1065-1831). Logistic binary multivariate regression analysis confirmed the association, even in the presence of other possible risk factors (CR: 1.580, 95% CI: 1.072-2.330).

CONCLUSION FOR PRACTICE

Birth by CD is one of the factors that are associated with the early development of overweight in preschoolers.

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.

Oral administration of maternal vaginal microbes at birth to restore gut microbiome development in infants born by caesarean section: A pilot randomised placebo-controlled trial

BACKGROUND

Birth by caesarean section (CS) is associated with aberrant gut microbiome development and greater disease susceptibility later in life. We investigated whether oral administration of maternal vaginal microbiota to infants born by CS could restore their gut microbiome development in a pilot single-blinded, randomised placebo-controlled trial (Australian New Zealand Clinical Trials Registry, ACTRN12618000339257).

METHODS

Pregnant women scheduled for a CS underwent comprehensive antenatal pathogen screening. At birth, healthy neonates were randomised to receive a 3 ml solution of either maternal vaginal microbes (CS-seeded, n = 12) or sterile water (CS-placebo, n = 13). Vaginally-born neonates were used as the reference control (VB, n = 22). Clinical assessments occurred within the first 2 h of birth, and at 1 month and 3 months of age. Infant stool samples and maternal vaginal extracts from CS women underwent shotgun metagenomic sequencing. The primary outcome was gut microbiome composition at 1 month of age. Secondary outcomes included maternal strain engraftment, functional potential of the gut microbiome, anthropometry, body composition, and adverse events.

FINDINGS

Despite the presence of viable microbial cells within transplant solutions, there were no observed differences in gut microbiome composition or functional potential between CS-seeded and CS-placebo infants at 1 month or 3 months of age. Both CS groups displayed the characteristic signature of low Bacteroides abundance, which contributed to a number of biosynthesis pathways being underrepresented when compared with VB microbiomes. Maternal vaginal strain engraftment was rare. Vaginal seeding had no observed effects on anthropometry or body composition. There were no serious adverse events associated with treatment.

INTERPRETATION

Our pilot findings question the value of vaginal seeding given that oral administration of maternal vaginal microbiota did not alter early gut microbiome development in CS-born infants. The limited colonisation of maternal vaginal strains suggest that other maternal sources, such as the perianal area, may play a larger role in seeding the neonatal gut microbiome.

FUNDING

Health Research Council of New Zealand, A Better Start - National Science Challenge.

Early-life gut microbiota and its connection to metabolic health in children: Perspective on ecological drivers and need for quantitative approach

The colonisation and development of the gut microbiota has been implicated in paediatric metabolic disorders via its powerful effect on host metabolic and immune homeostasis. Here we summarise the evidence from human studies on the early gut microbiota and paediatric overweight and obesity. Manipulation of the early gut microbiota may represent a promising target for countering the burgeoning metabolic disorders in the paediatric population, provided the assembly patterns of microbiota and their health consequences can be decoded. Therefore, in this review, we pay particular attention to the important ecological drivers affecting the community dynamics of the early gut microbiota. We then discuss the knowledge gaps in commonly studied exposures linking the gut microbiota to metabolic disorders, especially regarding maternal factors and antibiotic use. This review also attempts to give directions for future studies aiming to identify predictive and corrective measures for paediatric metabolic disorders based on the gut microbiota. Gut microbiota; Metabolism; Paediatric overweight and obesity; Ecological driver; Dynamics; Infants.

Caesarean delivery is associated with an absolute increase in the prevalence of overweight in the offspring: The SENDO project

AIM

The association between caesarean delivery and the risk of overweight/obesity in the offspring has been previously reported using conventional measures of association (relative risks or odds ratios). We aimed at refining the existing evidence by calculating the marginal effect of the exposure and estimating the unmeasured residual confounding.

METHODS

In the 'SEguimiento del Niño para un Desarrollo Óptimo' Project, a dynamic multipurpose paediatric cohort study, we collected information from parents through self-administered online questionnaires. We estimated the offspring's risk of overweight/obesity at age 4-6 years, associated with the type of delivery through marginal effect of the exposure. Unmeasured residual confounding was assessed using the E-value.

RESULTS

Among 407 participants (mean-age: 5.0 years (standard deviation: 0.9)), 86 (21.1%) were born by caesarean delivery. Children born by caesarean delivery had higher odds of overweight/obesity than those born vaginally. Subgroup analyses showed similar results. The multivariable adjusted marginal effect showed that caesarean delivery was associated with an 8.0% (95% confidence interval: 0.2-15.7) absolute increase in the prevalence of overweight/obesity. The estimated residual confounding showed an E-value of 4.03, higher than the OR obtained for all the confounding factors we accounted for.

CONCLUSIONS

Caesarean delivery was associated with an 8% absolute increase in the risk of overweight/obesity that is very unlikely explained by residual confounding.

Caesarean delivery is associated with increased blood pressure in young adult offspring

We examined the associations between caesarean section (CS) delivery and cardiovascular risk factors in young adults in Thailand. Participants were 632 offspring from a birth cohort in Chiang Mai (Northern Thailand), born in 1989–1990 and assessed in 2010 at a mean age of 20.6 years, including 57 individuals (9.0%) born by CS and 575 born vaginally. Clinical assessments included anthropometry, blood pressure (BP), carotid intima-media thickness, and fasting blood glucose, insulin, and lipid profile. Young adults born by CS had systolic BP (SBP) 6.2 mmHg higher (p < 0.001), diastolic BP 3.2 mmHg higher (p = 0.029), and mean arterial pressure (MAP) 4.1 mmHg higher (p = 0.003) than those born vaginally. After covariate adjustments, SBP and MAP remained 4.1 mmHg (p = 0.006) and 2.9 mmHg (p = 0.021) higher, respectively, in the CS group. The prevalence of abnormal SBP (i.e., pre-hypertension or hypertension) in the CS group was 2.5 times that of those born vaginally (25.0% vs 10.3%; p = 0.003), with an adjusted relative risk of abnormal SBP 1.9 times higher (95% CI 1.15, 2.98; p = 0.011). There were no differences in anthropometry (including obesity risk) or other metabolic parameters. In this birth cohort in Thailand, CS delivery was associated with increased blood pressure in young adulthood.

Addressing obesity in the first 1000 days in high risk infants: Systematic review

Early intervention is critical for addressing the challenge of childhood obesity. Yet many preventive interventions do not target infants most at risk of future overweight or obesity. This systematic review examines interventions delivered before 2 years that aim to ameliorate excess weight gain among infants at high risk of overweight or obesity, due to sociodemographic characteristics, parental weight or health status, infant feeding or health behaviours. We searched six databases for interventions: (a) delivered before age two, (b) specifically aimed at infants at high risk of childhood obesity and (c) that reported outcomes by weight status beyond 28 days. The search identified over 27,000 titles, and 49 papers from 38 studies met inclusion criteria: 10 antenatal interventions, 16 postnatal and 12 conducted both before and after birth. Nearly all targeted infant and/or maternal nutrition. Studies varied widely in design, obesity risk factors, outcomes and quality. Overall, nine interventions of varying quality reported some evidence of significantly improved child weight trajectory, although effects tended to diminish over time. Interventions that improved weight outcomes tended to engage parents for a longer period, and most offered health professional input and support. Two studies of limited quality reported significantly worse weight outcomes in the intervention group.

Gut microbiota comparison of vaginally and cesarean born infants exclusively breastfed by mothers secreting α1-2 fucosylated oligosaccharides in breast milk

BACKGROUND

Exclusive breastfeeding promotes beneficial modifications on the microbiota of cesarean born infants, but little is known about the role of specific breast milk components in this modulation. Women with an active FUT2 gene (called secretors) secrete α1-2 fucosylated human milk oligosaccharides (HMOs), which promote Bifidobacterium in the infant's gut and may modulate the microbiota of cesarean born infants.

OBJECTIVE

To compare the microbiota composition of cesarean and vaginally born infants breastfed by secretor mothers.

METHODS

Maternal secretor status was determined by the occurrence of 4 different α1-2 fucosylated HMOs in breast milk by LC-MS. The fecal microbiota composition from cesarean and vaginally born infants was analyzed by 16S rRNA gene sequencing and qPCR, stratified by the maternal secretor status, and compared.

RESULTS

Alpha and beta diversity were not significantly different in cesarean born, secretor-fed infants (CSe+) compared to vaginally born, secretor-fed infants (VSe+). There were no significant differences in the fecal relative abundance of Bifidobacterium between CSe+ and VSe+ infants, but the prevalence of the species B. longum was lower in CSe+. The fecal relative abundance of Bacteroides was also lower, while Akkermansia and Kluyvera were higher in CSe+ infants.

CONCLUSION

Cesarean and vaginally born infants fed with breast milk containing the α1-2 fucosylated HMOs fraction present similar amounts of Bifidobacterium in the feces, but differences are observed in other members of the microbiota.

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.

Delivery mode and altered infant growth at 1 year of life in India

BACKGROUND

Cesarean section (C-section) delivered infants are more likely to be colonized by opportunistic pathogens, resulting in altered growth. We examined whether C-section (elective/emergency) vs vaginal delivery was associated with altered weight and linear growth at 1 year of life.

METHODS

A total of 638 mother-infant pairs were included from MAASTHI cohort 2016-2019. Information on delivery mode was obtained from medical records. Based on WHO child growth standards, body mass index-forage z-score (BMI z) and length-for-age z-score (length z) were derived. We ran multivariable linear and Poisson regression models before and after multiple imputation.

RESULTS

The rate of C-section was 43.4% (26.5%: emergency, 16.9%: elective). Percentage of infant overweight was 14.9%. Compared to vaginal delivery, elective C-section was associated with β = 0.57 (95% CI 0.20, 0.95) higher BMI z. Also infants born by elective C-section had RR = 2.44 (95% CI 1.35, 4.41) higher risk of being overweight; no such association was found for emergency C-section. Also, elective C-section delivery was associated with reduced linear growth at 1 year after multiple imputation (β = -0.38, 95% CI -0.76, -0.01).

CONCLUSIONS

Elective C-section delivery might contribute to excess weight and also possibly reduced linear growth at 1 year of age in children from low- and middle-income countries.

IMPACT

Our study, in a low-income setting, suggests that elective, but not emergency, C-section is associated with excess infant BMI z at 1 year of age and elective C (C-section) was also associated with altered linear growth but only in multiple imputation analyses. Elective C-section was associated with a higher risk of being overweight at 1 year of age. Our results indicate that decreasing medically unnecessary elective C-section deliveries may help limit excess weight gain and stunted linear growth among infants.

Effect of Elective Cesarean Section on Children's Obesity From Birth to Adolescence: A Systematic Review and Meta-Analysis

BACKGROUND

Elective cesarean section (ECS) is the most common reason for the increasing cesarean section rate worldwide, and it is reported to be related to adverse short-term and long-term outcomes in both mothers and infants. Findings on the association between ECS and overweight and obesity in children are controversial in recent studies. Therefore, we conducted a systematic review and meta-analysis to examine the effect of ECS on offspring's overweight and obesity.

METHODS

PubMed, Science Direct, Web of Science, CNKI (China National Knowledge Infrastructure), Wanfang Database (in Chinese), and China Biology Medicine disc databases were searched using different combinations of three groups of keywords: "elective cesarean section," "overweight/obesity," and "children." Nine cohort studies and 11 independent risk estimates were finally identified.

RESULTS

We have observed significant association between ECS and children's obesity, the total pooled risk ratio (RR) being 1.10 (95% CI: 1.01-1.18; I ² = 32.4%). In subgroup analysis, ECS was found to be associated with the occurrence of obesity in preschoolers (RR = 1.12, 95% CI: 1.02-1.22; I ² = 16.8%). Furthermore, it revealed that ECS was related with the high risk of children's obesity where the rate of ECS exceeded 10%. No significant association was observed between ECS and children's overweight, and the RR was 1.12 (95% CI: 0.94-1.30; I ² = 55.6%).

CONCLUSIONS

Overall, it indicated that children born via ECS had an increased risk of later-life obesity. Given the global increase in childhood obesity, our findings would provide evidence-based reference for early life intervention on children's obesity.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021267211, identifier: CRD42021267211.

Mode of delivery, type of labor, and measures of adiposity from childhood to teenage: Project Viva

Background:

Cesarean delivery has been linked with childhood obesity. Few studies have examined if this association is attenuated if there is labor prior to delivery. The objective of this current analysis was to examine the association of cesarean vs. vaginal delivery with measures of childhood adiposity, and whether the association differs by labor type (spontaneous, induced, or absent) preceding cesarean delivery.

Methods:

We ascertained delivery mode and type of labor from medical records in 1443 mother-child dyads from Project Viva with adiposity measures from at least 1 follow-up visit (3369 total observations) in early childhood (median age 3.2y), mid-childhood (median 7.7y), or early teen (median 12.9y). Child adiposity outcomes were CDC age- and sex-specific body mass index (BMI) z-scores, sum of subscapular and triceps skinfold thicknesses (SS+TR; mm), and waist circumference (cm). We used linear regression models with generalized estimating equation estimates adjusted for maternal age, education, race/ethnicity, pre-pregnancy BMI, rate of gestational weight gain, and child sex and age at outcome.

Results:

A total of 333 (23%) women delivered via cesarean, including 155 (11%) with spontaneous labor, 74 (5%) with induced labor, 99 (7%) with no labor, and 5 (<1%) with unknown labor status. Compared to vaginal-delivered children, cesarean-delivered children had higher BMI-z (0.15, 95% CI: 0.04, 0.26); and non-significantly higher waist circumference (0.50 cm, 95% CI: −0.34, 1.34) and SS+TR (0.47 mm, 95% CI: −0.52, 1.46). Cesarean deliveries that were preceded by spontaneous labor were not associated with childhood BMI-z (0.08, 95% CI: −0.07, 0.23), waist circumference (−0.12 cm, 95% CI: −1.09, 0.85), or SS+TR (−0.25 mm, 95% CI: −1.44, 0.93), as compared to vaginal deliveries.

Conclusion:

Cesarean delivery was associated with higher childhood BMI-z, and although waist circumference and SS+TR trended in the same direction, these associations were not significant. Cesarean delivery preceded by spontaneous labor was not associated with adiposity outcomes.

Association between cesarean delivery types and obesity in preadolescence

Background/Objectives:

The association between mode of delivery and childhood obesity remains inconclusive. Because few studies have separated C-section types (planned or unplanned C-section), our objective was to assess how these subtypes relate to pre-adolescent obesity.

Subjects/Methods:

The study consisted of 570 maternal-child pairs drawn from the WHEALS birth cohort based in Detroit, Michigan. Children were followed-up at 10 years of age where a variety of anthropometric measurements were collected. Obesity was defined based on BMI percentile (≥95th percentile), as well as through gaussian finite mixture modeling on the anthropometric measurements. Risk ratios (RRs) and 95% confidence intervals (CIs) for obesity comparing planned and unplanned C-sections to vaginal deliveries were computed, which utilized inverse probability weights to account for loss to follow-up and multiple imputation for covariate missingness. Mediation models were fit to examine the mediation role of breastfeeding.

Results:

After adjusting for marital status, maternal race, prenatal tobacco smoke exposure, maternal age, maternal BMI, any hypertensive disorders during pregnancy, gestational diabetes, prenatal antibiotic use, child sex, parity, and birthweight z-score, children born via planned C-section had 1.77 times higher risk of obesity (≥95th percentile), relative to those delivered vaginally ((95% CI)=(1.16,2.72); p=0.009). No association was found comparing unplanned C-section to vaginal delivery (RR (95% CI)=0.75 (0.45, 1.23); p=0.25). Results were similar but slightly stronger when obesity was defined by anthropometric class (RR (95% CI)=2.78 (1.47, 5.26); p=0.002). Breastfeeding did not mediate the association between mode of delivery and obesity.

Conclusions:

These findings indicate that children delivered via planned C-section—but not unplanned C-section—have a higher risk of pre-adolescent obesity, suggesting that partial labor or membrane rupture (typically experienced during unplanned C-section delivery) may offer protection. Additional research is needed to understand the biological mechanisms behind this effect, including whether microbiological differences fully or partially account for the association.

Engineering the Gut Microbiome for Treatment of Obesity: A Review of Current Understanding and Progress

Obesity is a complex, multifactorial disease that is increasing in prevalence despite extensive research and efforts to curb it. Over the last decade, gut microbiome has emerged as an important contributor to the pathogenesis of obesity. Microbiome profile is altered in obese phenotype and the causative role of microbiome in obesity is demonstrated in fecal microbiota transplantation studies. Herein, recent evidences supporting the role of gut microbiome in obesity and the current therapies designed to engineer gut microbiome for treatment of obesity will be reviewed. The microbial enterotypes associated with obesity is outlined, and the gut microbiota-driven metabolism and low-grade inflammation linking gut microbiome and obesity is examined. How the different intrinsic and extrinsic factors such as host genetics, mode of childbirth delivery, diet, lifestyle habits and use of antibiotics influence the composition of the gut microbiome in the development of obesity is evaluated. Also, the efficacy of current microbiome-based therapies in the forms of prebiotics, probiotics and engineered microbes that are used to manipulate gut microbiome in treating obesity is discussed.

The impact of general anesthesia on mother-infant bonding for puerperants who undergo emergency cesarean deliveries

Background Mother-infant bonding is an emerging perinatal issue. While emergency cesarean deliveries are associated with a risk of bonding disorders, the mode of anesthesia used for emergency cesarean deliveries has never been studied in this context. We aimed to investigate the impact of administering general anesthesia and neuraxial anesthesia to women undergoing cesarean deliveries on mother-infant bonding. Methods This was a retrospective, propensity score-matched multivariable analysis of 457 patients who underwent emergency cesarean deliveries between February 2016 and January 2019 at a single teaching hospital in Japan. The Mother-Infant Bonding Scale (MIBS) scores at hospital discharge and the 1-month postpartum outpatient visit were evaluated in the general anesthesia and the neuraxial anesthesia groups. A high score on the MIBS indicates impaired mother-infant bonding. Results The primary outcome was the MIBS score at hospital discharge in propensity score-matched women. After propensity score matching, the median [interquartile range (IQR)] MIBS scores were significantly higher in the general anesthesia group than those in the neuraxial anesthesia group at hospital discharge [2 (1-4) vs. 2 (0-2); P = 0.015] and at the 1-month postpartum outpatient visit [1 (1-3) vs. 1 (0-2); P = 0.046]. In linear regression analysis of matched populations, general anesthesia showed a significant and positive association with the MIBS scores at hospital discharge [beta coefficient 0.867 (95% confidence interval [CI] 0.147-1.59); P = 0.019] but not at the 1-month postpartum outpatient visit [0.455 (-0.134 to 1.044); P = 0.129]. Conclusion General anesthesia for emergency cesarean delivery is an independent risk factor associated with impaired mother-infant bonding.

Association of Cesarean Birth with Body Mass Index Trajectories in Adolescence

Background: This study aimed to identify patterns of body mass index (BMI) changes in adolescence and to assess whether delivery mode (Cesarean and vaginal delivery) was associated with BMI trajectories. Methods: This study was conducted among 569 adolescents aged 10–15 years that resided in the city of Zibo, China. The height and weight of each participant were repeatedly measured at 10, 11, 12, 13, 14 and 15 years. Group based trajectory modeling (GBTM) was used to estimate BMI change trajectories, and multinomial logistic regression was conducted to evaluate the independent association of delivery mode and BMI trajectory classes. Results: Of the 569 participants, 407 (71.5%) were vaginal deliveries and 162 (28.5%) were Cesarean deliveries. Five distinct long-term BMI trajectories were identified: “persistent healthy weight” (57.5%), “persistent underweight” (6.5%), “obesity to healthy weight” (7.8%), “progressive overweight” (10.6%), “progressive obesity” (17.6%). Adjusted multinomial logistic models revealed a twofold increase in risks between ages 10–15 years of “progressive obesity” trajectory (OR = 2.50, 95% CI: 1.42, 4.41) for children born through Cesarean section compared with vaginal birth. Conclusions: Five distinct long-term BMI trajectories were identified during adolescence in our research, and we confirmed that Cesarean birth was significantly increased the risk of “progressive obesity” trajectory but not the “obesity to healthy weight” trajectory.

Associations Between Delivery Mode and Early Childhood Body Mass Index Z-Score Trajectories: A Retrospective Analysis of 2,685 Children From Mothers Aged 18 to 35 Years at Delivery

Objective: To investigate the association between cesarean delivery (CD) and trajectory patterns of age- and sex-specific body mass index (BMI) z-score in early childhood. Methods: A retrospective cohort study was conducted among 2,685 children whose maternal age at the time of birth was between 18 and 35 years, and birth data and anthropometric measurement data during their ages 3-60 months were collected. A group-based trajectory modeling approach was used to identify distinct BMI z-score trajectories, and multinomial logistic regressions were applied to estimate the associations among CD (both elective and non-elective combined), elective and non-selective CD, and BMI z-score trajectory classes. Results: Of the 2,685 participants, 46.5% (N = 1,248) were born by vaginal delivery (VD), 20.7% (N = 556) by elective CD, and 32.8% (N = 881) by non-elective CD. Five BMI z-score trajectory patterns were identified, and they were "increasing from moderate to high" (10.1%, n = 270), "increasing from mild to moderate" (34.2%, n = 919), "increasing from low to high" (10.5%, n = 283), "stable mild" (30.1%, n = 808), and "stable low" (15.1%, n = 405) groups. Compared with children delivered by VD, those who delivered by CD (both elective and non-elective combined), elective CD, and non-elective CD were associated with the "increasing from moderate to high" trajectory [odds ratio (OR) = 1.61, 95% confidence interval (CI): 1.13-2.29; OR = 1.64, 95%CI: 1.06-2.54; and OR = 1.59, 95%CI: 1.05-2.39, respectively] and were also associated with the "increasing from low to high" trajectory (OR = 1.60, 95%CI: 1.17-2.19, OR = 1.75, 95%CI: 1.16-2.63; and OR = 1.53, 95%CI: 1.00-2.34, respectively). Conclusion: Both elective and non-elective CD were associated with the risk of accelerated weight gain in early childhood.

Elective and nonelective cesarean section and obesity among young adult male offspring: A Swedish population-based cohort study

BACKGROUND

Previous studies have suggested that cesarean section (CS) is associated with offspring overweight and obesity. However, few studies have been able to differentiate between elective and nonelective CS, which may differ in their maternal risk profile and biological pathway. Therefore, we aimed to examine the association between differentiated forms of delivery with CS and risk of obesity in young adulthood.

METHODS AND FINDINGS

Using Swedish population registers, a cohort of 97,291 males born between 1982 and 1987 were followed from birth until conscription (median 18 years of age) if they conscripted before 2006. At conscription, weight and height were measured and transformed to World Health Organization categories of body mass index (BMI). Maternal and infant data were obtained from the Medical Birth Register. Associations were evaluated using multinomial and linear regressions. Furthermore, a series of sensitivity analyses were conducted, including fixed-effects regressions to account for confounders shared between full brothers. The mothers of the conscripts were on average 28.5 (standard deviation 4.9) years old at delivery and had a prepregnancy BMI of 21.9 (standard deviation 3.0), and 41.5% of the conscripts had at least one parent with university-level education. Out of the 97,291 conscripts we observed, 4.9% were obese (BMI ≥ 30) at conscription. The prevalence of obesity varied slightly between vaginal delivery, elective CS, and nonelective CS (4.9%, 5.5%, and 5.6%, respectively), whereas BMI seemed to be consistent across modes of delivery. We found no evidence of an association between nonelective or elective CS and young adulthood obesity (relative risk ratio 0.96, confidence interval 95% 0.83-1.10, p = 0.532 and relative risk ratio 1.02, confidence interval 95% 0.88-1.18, p = 0.826, respectively) as compared with vaginal delivery after accounting for prepregnancy maternal BMI, maternal diabetes at delivery, maternal hypertension at delivery, maternal smoking, parity, parental education, maternal age at delivery, gestational age, birth weight standardized according to gestational age, and preeclampsia. We found no evidence of an association between any form of CS and overweight (BMI ≥ 25) as compared with vaginal delivery. Sibling analysis and several sensitivity analyses did not alter our findings. The main limitations of our study were that not all conscripts had available measures of anthropometry and/or important confounders (42% retained) and that our cohort only included a male population.

CONCLUSIONS

We found no evidence of an association between elective or nonelective CS and young adulthood obesity in young male conscripts when accounting for maternal and prenatal factors. This suggests that there is no clinically relevant association between CS and the development of obesity. Further large-scale studies are warranted to examine the association between differentiated forms of CS and obesity in young adult offspring.

TRIAL REGISTRATION

Registered as observational study at ClinicalTrials.gov Identifier: NCT03918044.

Caesarean section delivery and childhood obesity in a British longitudinal cohort study

Background

Several studies reported an association between Caesarean section (CS) birth and childhood obesity. However, there are several limitations in the current literature. These include an inability to distinguish between planned and emergency CS, small study sample sizes and not adjusting for pre-pregnancy body-mass-index (BMI). We examined the association between CS delivery and childhood obesity using the United Kingdom Millennium Cohort Study (MCS).

Methods

Mother-infant pairs were recruited into the MCS. Use of sampling weights ensured the sample was representative of the population. The exposure was categorised as normal vaginal delivery (VD) [reference], assisted VD, planned CS and emergency CS. Childhood obesity prevalence, at age three, five, seven, eleven and fourteen years was calculated using the International Obesity Taskforce criteria. Mixed-effects linear regression models were fitted with associations adjusted for several potential confounders like maternal age, pre-pregnancy BMI, education and infant macrosomia. Linear regression models were fitted evaluating body fat percentage (BF%), at age seven and fourteen years.

Results

Of the 18,116 infants, 3872 (21.4%) were delivered by CS; 9.2% by planned CS. Obesity prevalence was 5.4%, 5.7%, 6.5%, 7.1% and 7.6% at age three, five, seven, eleven and fourteen years respectively. The mixed-effects linear regression model showed no association between planned (adjusted mean difference = 0.00; [95% confidence interval (CI) -0.10; 0.10], p-value = 0.97) or emergency CS (adjusted mean difference = 0.08; [95% CI -0.01; 0.17], p-value = 0.09) and child BMI. At age seven years, there was no association between planned CS and BF% (adjusted mean difference = 0.13; [95% CI -0.23; 0.49]); there was no association at age fourteen years.

Conclusions

Infants born by planned CS did not have a significantly higher BMI or BF% compared to those born by normal VD. This may suggest that the association, described in the literature, could be due to the indications/reasons for CS birth or residual confounding.

Caesarean section delivery and childhood obesity: evidence from the growing up in New Zealand cohort

Background

Epidemiological studies have reported conflicting results in the association between Caesarean section (CS) birth and childhood obesity. Many of these studies had small sample sizes, were unable to distinguish between elective/planned and emergency CS, and did not adjust for the key confounder maternal pre-pregnancy body mass index (BMI). We investigated the association between CS delivery, particularly elective/planned and childhood obesity, using the Growing Up in New Zealand prospective longitudinal cohort study.

Methods

Pregnant women planning to deliver their babies on the New Zealand upper North Island were invited to participate. Mode of delivery was categorised into spontaneous vaginal delivery (VD) (reference), assisted VD, planned CS and emergency CS. The main outcome was childhood obesity defined according to the International Obesity Taskforce criteria at age 24 and 54 months. Multinomial logistic regression and mixed-effects linear regression models were fitted with associations adjusted for several potential confounders.

Results

Of the 6599 infants, 1532 (23.2%) were delivered by CS. At age 24 months, 478 (9.3%) children were obese. There was a statistically significant association between planned CS adjusted relative risk ratio (aRRR=1.59; (95% CI 1.09 to 2.33)) and obesity but not for emergency CS (aRRR=1.27; (95% CI 0.89 to 1.82)). At age 54 months there was no association between planned CS (aRRR=0.89; (95% CI 0.54 to 1.45)) and obesity as well as for emergency CS (aRRR=1.19; (95% CI 0.80 to 1.77)). At all-time points those born by planned CS had a higher mean BMI (adjusted mean difference=0.16; (95% CI 0.00 to 0.31), p=0.046).

Conclusions

Planned CS was an independent predictor of obesity in early childhood. This suggests that birth mode influences growth, at least in the short term. This association occurred during a critical phase of human development, the first 2 years of life, and if causal might result in long-term detrimental cardiometabolic changes.

Association of elective cesarean delivery with metabolic measures in childhood: A prospective cohort study in China

BACKGROUND AND AIMS

Cesarean delivery may increase the risk of childhood obesity, a precursor of metabolic syndrome (MetS). We aimed to investigate the association of elective cesarean delivery (ElCD) with MetS and its components in a Chinese birth cohort.

METHODS AND RESULTS

This cohort included 1467 children (737 delivered by ElCD and 730 by spontaneous vaginal delivery [SVD]) who were followed up at the age of 4-7 years in 2013. MetS was defined as the presence of ≥3 components: central obesity, hypertriglyceridemia, low high-density lipoprotein (HDL), high fasting glucose, and hypertension. Of the 1467 children, 93 (6.3%) were categorized as having MetS: 50 (6.8%) delivered by ElCD and 43 (5.9%) by SVD. After multivariable adjustment, ElCD was not associated with MetS (adjusted odds ratio [AOR] 1.15, 95% confidence interval [CI] 0.74, 1.78) or certain components including hypertriglyceridemia, low HDL, and high fasting glucose but was associated with central obesity (AOR 1.33, 95% CI 1.02, 1.72) and hypertension (AOR 1.50, 95% CI 1.15, 1.96), as well as higher levels of total cholesterol (3.43 vs. 3.04 mmol/L; P < 0.001), low-density lipoprotein-cholesterol (1.77 vs. 1.67 mmol/L, P = 0.002), fasting glucose (5.08 vs. 5.02 mmol/L, P = 0.022), systolic (97.57 vs. 94.69 mmHg, P < 0.001)/diastolic blood pressure (63.72 vs. 62.24 mmHg, P < 0.001), and BMI (15.46 vs. 14.83 kg/m², P < 0.001) than SVD.

CONCLUSIONS

ElCD is not associated with MetS in early to middle childhood but is associated with its components including central obesity and hypertension, as well as various continuous indices.