Cohort Profile: The Etude Epidémiologique sur les Petits Ages Gestationnels-2 (EPIPAGE-2) preterm birth cohort

Screening preterm-born infants for autistic traits may help to identify social communication difficulties at five years of age

AIM

This study compared neurodevelopmental screening questionnaires completed when preterm-born children reached 2 years of corrected age with social communication skills at 5.5 years of age.

METHODS

Eligible subjects were born in 2011 at 24-34 weeks of gestation, participated in a French population-based epidemiological study and were free of motor and sensory impairment at 2 years of corrected age. The Ages and Stages Questionnaire (ASQ) and the Modified Checklist for Autism in Toddlers (M-CHAT) were used at 2 years and the Social Communication Questionnaire (SCQ) at 5.5 years of age.

RESULTS

We focused on 2119 children. At 2 years of corrected age, the M-CHAT showed autistic traits in 20.7%, 18.5% and 18.2% of the children born at 24-26, 27-31 and 32-34 weeks of gestation, respectively (p = 0.7). At 5.5 years of age, 12.6%, 12.7% and 9.6% risked social communication difficulties, with an SCQ score ≥90th percentile (p = 0.2). A positive M-CHAT score at 2 years was associated with higher risks of social communication difficulties at 5.5 years of age (odds ratio 3.46, 95% confidence interval 2.04-5.86, p < 0.001). Stratifying ASQ scores produced similar results.

CONCLUSION

Using parental neurodevelopmental screening questionnaires for preterm-born children helped to identify the risk of later social communication difficulties.

Birth weight and head circumference discordance and outcome in preterms: results from the EPIPAGE-2 cohort

OBJECTIVE

To determine whether the relative measurement of birth weight (BW) and head circumference (HC) in preterm infants is associated with neurological outcomes.

METHODS

The EPIPAGE-2 Study included 3473 infants born before 32 weeks' gestation, classified based on their Z-score of BW and HC on the Fenton curves as concordant (≤1 SD apart) or discordant (>1 SD difference). We defined four mutually exclusive categories: discordant smaller BW (sBW) with BW-1SD and concordant small measurement (CsM) with BW and HC concordant and both ≤-1SD. Neurological outcomes at 5.5 years were evaluated with standard tests.

RESULTS

2592 (74.8%) preterm neonates were categorised as CM, 258 (7.4%) CsM, 378 (10.9%) sHC and 239 (6.9%) sBW. Compared with the CM children, those born with CsM had significantly higher risks of cognitive deficiency (adjusted OR (aOR) 1.3, 95% CI (1.0 to 2.0)), developmental coordination disorders (aOR 2.6 (1.5 to 4.4)) and need for special school services (aOR 2.3 (1.5 to 3.7)). Those born with sBW had significantly lower risk of cognitive deficiency (aOR 0.6 (0.4 to 0.9)) and the sHC group significantly higher risk of developmental coordination disorders (aOR 1.8 (1.0 to 3.2)).

CONCLUSIONS

The relative discordance of these preterm infants' BW and HC was associated with their neurological outcomes. It merits further exploration as an indirect indicator of development.

TRIAL REGISTRATION NUMBER

NCT03078439.

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

BACKGROUND

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

[Epidemiology and risk factors for preterm births in north-western Algeria]

Introduction

preterm births continue to be the main cause of infant and child mortality as well as sensory-motor disabilities and neurodevelopmental difficulties worldwide. The rate of preterm births has been rising, in particular in Algeria. The purpose of this study is to determine the frequency of preterm births in the Oran Wilaya and to identify risk factors.

Methods

we used data from a multicentre cross-sectional study carried out in all Public Maternity Hospitals in the Oran Wilaya (13). The study included parturient women who had given birth to a live and/or stillborn child (with birthweights ≥500 g), whose gestational age was greater than or equal to 24-36 weeks of amenorrhoea. Mothers´ demographic, medical and socio-behavioural factors were recorded. Logistic regression was used to study predictors of prematurity.

Results

preterm birth rate was 9.9% (45/452). The average age of patients was 30.4±6 years; multiple pregnancies accounted for 2.2% of births. Factors related to prematurity were the risk of premature labour (aOR=4.68; 95% CI: 2.27-9.64), the lack of clinical monitoring of pregnancy (OR=2.83; CI 95%: 1.83-6.05) and gestational hypertension (aOR = 3.69, 95% CI: 1.83-8.8).

Conclusion

the rate of preterm births is in line with the rate observed in neighbouring countries. The study identified predictive factors, some of which are already targeted by the national perinatal program. However, it is essential to continue to lead efforts to improve the monitoring and management of pregnancies and premature births at all levels of care.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSIONS

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

Association between gut microbiota at 3.5 years of age and body mass index at 5 years: results from two French nationwide birth cohorts

BACKGROUND/OBJECTIVES

The relationship between gut microbiota and changes in body mass index (BMI) or pediatric overweight in early life remains unclear, and information regarding the preterm population is scarce. This study aimed to investigate how the gut microbiota at 3.5 years of age is associated with (1) later BMI at 5 years, and (2) BMI z-score variations between 2 and 5 years in children from two French nationwide birth cohorts.

SUBJECTS/METHODS

Bacterial 16S rRNA gene sequencing was performed to profile the gut microbiota at 3.5 years of age in preterm children (n = 143, EPIPAGE 2 cohort) and late preterm/full-term children (n = 369, ELFE cohort). The predicted abundances of metabolic functions were computed using PICRUSt2. Anthropometric measurements were collected at 2 and 5 years of age during medical examinations or retrieved from children's health records. Statistical analyses included multivariable linear and logistic regressions, random forest variable selection, and MiRKAT.

RESULTS

The Firmicutes to Bacteroidetes (F/B) ratio at 3.5 years was positively associated with the BMI z-score at 5 years. Several genera were positively ([Eubacterium] hallii group, Fusicatenibacter, and [Eubacterium] ventriosum group) or negatively (Eggerthella, Colidextribacter, and Ruminococcaceae CAG-352) associated with the BMI z-scores at 5 years. Some genera were also associated with variations in the BMI z-scores between 2 and 5 years of age. Predicted metabolic functions, including steroid hormone biosynthesis, biotin metabolism, glycosaminoglycan degradation, and amino sugar and nucleotide sugar metabolism, were associated with lower BMI z-scores at 5 years. The unsaturated fatty acids biosynthesis pathway was associated with higher BMI z-scores.

CONCLUSIONS

These findings indicate that the gut microbiota at 3.5 years is associated with later BMI during childhood, independent of preterm or term birth, suggesting that changes in the gut microbiota that may predispose to adult obesity begin in early childhood.

Neurodevelopment at age 5.5 years according to Ages & Stages Questionnaire at 2 years' corrected age in children born preterm: the EPIPAGE-2 cohort study

OBJECTIVE

To report neurodevelopment at age 5.5 years according to developmental delay screening with the Ages & Stages Questionnaire (ASQ) in late infancy in preterm-born children.

DESIGN

Population-based cohort study, EPIPAGE-2.

SETTING

France, 2011-2017.

PARTICIPANTS

2504 children born at 24-26, 27-31 and 32-34 weeks, free of cerebral palsy, deafness or blindness at 2 years' corrected age.

MAIN OUTCOME MEASURES

Moderate/severe, mild or no disability at age 5.5 years using gross and fine motor, sensory, cognitive and behavioural evaluations. Results of the ASQ completed between 22 and 26 months' corrected age described as positive screening or not.

RESULTS

Among 2504 participants, 38.3% had ASQ positive screening. The probability of having moderate/severe or mild disability was higher for children with ASQ positive versus negative screening: 14.2% vs 7.0%, adjusted OR 2.5 (95% CI 1.8 to 3.4), and 37.6% vs 29.7%, adjusted OR 1.5 (1.2 to 1.9). For children with ASQ positive screening, the probability of having neurodevelopmental disabilities at age 5.5 years was associated with the number of domain scores below threshold, very low gestational age and severe neonatal morbidities. For children with ASQ negative screening, this probability was increased for boys and children born small-for-gestational age. For both groups, maternal level of education was strongly associated with outcomes.

CONCLUSION

In preterm-born children, ASQ screening at 2 years' corrected age was associated with neurodevelopmental disabilities at age 5.5 years. However, other factors should be considered when interpreting the ASQ data to draw further follow-up.

TRIAL REGISTRATION NUMBER

2016-A00333-48.

The interrelatedness of cognitive abilities in very preterm and full-term born children at 5.5 years of age: a psychometric network analysis approach

BACKGROUND

Very preterm (VP) birth is associated with a considerable risk for cognitive impairment, putting children at a disadvantage in academic and everyday life. Despite lower cognitive ability on the group level, there are large individual differences among VP born children. Contemporary theories define intelligence as a network of reciprocally connected cognitive abilities. Therefore, intelligence was studied as a network of interrelated abilities to provide insight into interindividual differences. We described and compared the network of cognitive abilities, including strength of interrelations between and the relative importance of abilities, of VP and full-term (FT) born children and VP children with below-average and average-high intelligence at 5.5 years.

METHODS

A total of 2,253 VP children from the EPIPAGE-2 cohort and 578 FT controls who participated in the 5.5-year-follow-up were eligible for inclusion. The WPPSI-IV was used to measure verbal comprehension, visuospatial abilities, fluid reasoning, working memory, and processing speed. Psychometric network analysis was applied to analyse the data.

RESULTS

Cognitive abilities were densely and positively interconnected in all networks, but the strength of connections differed between networks. The cognitive network of VP children was more strongly interconnected than that of FT children. Furthermore, VP children with below average IQ had a more strongly connected network than VP children with average-high IQ. Contrary to our expectations, working memory had the least central role in all networks.

CONCLUSIONS

In line with the ability differentiation hypothesis, children with higher levels of cognitive ability had a less interconnected and more specialised cognitive structure. Composite intelligence scores may therefore mask domain-specific deficits, particularly in children at risk for cognitive impairments (e.g., VP born children), even when general intelligence is unimpaired. In children with strongly and densely connected networks, domain-specific deficits may have a larger overall impact, resulting in lower intelligence levels.

Five-year outcomes for extremely preterm babies with active perinatal management: A clinical prediction model

OBJECTIVE

To develop and validate a clinical prediction model for outcomes at 5 years of age for children born extremely preterm and receiving active perinatal management.

DESIGN

The EPIPAGE-2 national prospective cohort.

SETTING

France, 2011.

POPULATION

Live-born neonates between 24+0 and 26+6  weeks of gestation who received active perinatal management (i.e. birth in a tertiary-level hospital, with antenatal steroids and resuscitation at birth).

METHODS

A prediction model using logistic modelling, including gestational age, small-for gestational-age (SGA) status and sex, was developed. Model performance was assessed through calibration and discrimination, with bootstrap internal validation.

MAIN OUTCOME MEASURES

Survival without moderate or severe neurodevelopmental disability (NDD) at 5 years.

RESULTS

Among the 557 neonates included, 401 (72%) survived to 5 years, of which 59% survived without NDD (95% CI 54% to 63%). Predicted rates of survival without NDD ranged from 45% (95% CI 33% to 57%), to 56% (95% CI 49% to 64%) to 64% (95% CI 57% to 70%) for neonates born at 24, 25 and 26 weeks of gestation, respectively. Predicted rates of survival without NDD were 47% (95% CI 18% to 76%) and 62% (95% CI 49% to 76%) for SGA and non-SGA children, respectively. The model showed good calibration (calibration slope 0.85, 95% CI 0.54 to 1.16; calibration-in-the-large -0.0123, 95% CI -0.25 to 0.23) and modest discrimination (C-index 0.59, 95% CI 0.53 to 0.65).

CONCLUSIONS

A simple prediction model using three factors easily known antenatally may help doctors and families in their decision-making for extremely preterm neonates receiving active perinatal management.

Maternal health-related quality of life at 1 year after a preterm birth: role of socioeconomic status at birth

BACKGROUND

Maternal problems in the postpartum period may lead to suboptimal long-term health for women and could affect mother-child attachment. Social disadvantage is a risk factor for preterm birth, which carries its own burden of health issues and stress. The main aim of this study was to investigate the role for social factors in mothers' physical and emotional health-related quality of life (HRQoL) at 1 year after a preterm birth.

METHODS

EPIPAGE-2 is a French nationwide, prospective, population-based cohort of preterm children born before 35 weeks' gestation (N=3614 women). At birth, detailed data on the family's social status were collected. At 1 year after birth, mothers completed a mailed questionnaire to report information on their HRQoL, assessed by the Medical Outcomes Study 12-item Short Form. We used multivariate linear regression models to assess the association between social factors and maternal HRQoL.

RESULTS

At 1 year after childbirth, the emotional HRQoL of mothers of preterm children was worse than their physical HRQoL, even in women without any previous signs of psychological distress at the infant's discharge from hospital. Baseline social characteristics were the most important factors influencing the physical component of HRQoL. None of the studied social factors had any clear association with the mental component of HRQoL.

CONCLUSION

Our study underlines the importance of social disadvantage during pregnancy as risk factors for poor physical HRQoL at 1 year after a preterm birth.

Timing of antenatal corticosteroids and survival without neurologic disabilities at 5½ years in children born before 35 weeks of gestation

BACKGROUND

The efficacy of antenatal corticosteroids for neonatal preterm complications wanes beyond 7 days after treatment. The neurodevelopmental effects of longer treatment-to-birth intervals have not been adequately evaluated.

OBJECTIVE

This study aimed to assess the impact of antenatal corticosteroid timing on survival without moderate or severe neurologic disabilities at 5½ years.

STUDY DESIGN

This was a secondary analysis of the EPIPAGE-2 study, a national population-based cohort (France) that recruited neonates in 2011 and followed them up at 5½ years (results first reported in 2021). Participants were children born alive between 24+0 and 34+6 weeks, with a complete corticosteroid course, delivery >48 hours after the first injection, and neither limitation of care decided before birth nor severe congenital malformation. The study included 2613 children, 2427 of whom were alive at 5½ years; 71.9% (1739/2427) had a neurologic assessment at this age; 1537 had a clinical examination (complete for 1532), and 202 were assessed with a postal questionnaire. Exposure was defined as the interval between the first injection of the last antenatal corticosteroid course and delivery in days, studied in 2 categories (days 3-7 and after day 7), in 4 categories (days 3-7, 8-14, 15-21, and after day 21), and continuously in days. The main outcome was survival at 5½ years without moderate/severe neurologic disabilities, defined as moderate/severe cerebral palsy, or unilateral or bilateral blindness or deafness, or Full-Scale Intelligence Quotient 2 standard deviations below the mean. A multivariate analysis with a generalized estimated equation logistic regression model assessed the statistical association between the main outcomes and the interval from the first corticosteroid injection of the last course to birth. Multivariate analyses were adjusted for potential confounders, defined with a directed acyclic graph: gestational age in days, number of corticosteroid courses, multiple pregnancy, and cause of prematurity in 5 categories. Because neurologic follow-up was complete in only 63.2% of cases (1532/2427), the analyses used imputed data.

RESULTS

Among 2613 children, 186 died between birth and 5½ years. Overall survival was 96.6% (95% confidence interval, 95.9-97.0), and survival without moderate or severe neurologic disabilities was 86.0% (95% confidence interval, 84.7-87.0). Survival without moderate or severe neurologic disabilities was lower after day 7 (85.0%) than during the interval from day 3 to day 7 (87.0%) (adjusted odds ratio, 0.70; 95% confidence interval, 0.54-0.89).

CONCLUSION

The association of a >7-day interval between antenatal corticosteroid administration and birth with a lower rate of survival without moderate or severe neurologic disabilities among children aged 5½ years emphasizes the importance of better targeting women at risk of preterm delivery to optimize the timing and thus benefits of treatment.

SARS-CoV-2 seroprevalence in French 9-year-old children and their parents after the first lockdown in 2020

Introduction

Children have been significantly less affected by COVID-19 than adults and presented with milder and less symptomatic forms of the disease. However, there has been suggestion that children older than 10 years and adolescents exhibits features closer to that of young adults. Most studies combine children in different age-groups and lack sufficient numbers to explore in detail age specificities. We report data on a population-based sample of 2,555 children at the pivotal age of 9 years.

Methods

In April 2020, the participants in two French nationwide cohorts of children, Elfe and Epipage2, were invited to take part into an online survey about Covid related symptoms and family life during the lockdown. A second questionnaire was sent on May 5. This questionnaire also proposed to the child included in the cohort and to one of his/her parents to take part into a capillary blood collection for Covid serology. Families who agreed to the serological survey were sent kits for dried blood spots self-sampling (DBS) with instructions. Samples were processed with a commercial Elisa test (Euroimmun®, Lübeck, Germany) to detect anti-SARS-CoV-2 antibodies (IgG) directed against the S1 domain of the spike protein of the virus.

Results

Children's acceptance rate for the serological survey was around 60%. 2,555 serological results were analyzed. The weighted prevalence of a positive Elisa Spike serology was 2.8% in 9 yr-old children (95% CI: 1.7%-4.0%). Positive serology was found in 8.6% (7.4%-9.7%) of parents who provided blood. There was a significant association (p < 0.001) between serology of the child and parent from the same household with an odds ratio of 13.8 (7.9-24.2).

Discussion

We have shown that 9-yr old children had a lower susceptibility to SARS-Cov2 infection than adults with the initial Chinese strain, similar to younger children and estimated that around 3% of them have developed antibodies against SARS-Cov2 in France after the first wave of the Covid-19 epidemics.

Circumstances, causes and timing of death in extremely preterm infants admitted to NICU: The EPIPAGE-2 study

AIM

To describe the circumstances, causes and timing of death in extremely preterm infants.

METHODS

We included from the EPIPAGE-2 study infants born at 24-26 weeks in 2011 admitted to neonatal intensive care units (NICU). Vital status and circumstances of death were used to define three groups of infants: alive at discharge, death with or without withholding or withdrawing life-sustaining treatment (WWLST). The main cause of death was classified as respiratory disease, necrotizing enterocolitis, infection, central nervous system (CNS) injury, other or unknown.

RESULTS

Among 768 infants admitted to NICU, 224 died among which 89 died without WWLST and 135 with WWLST. The main causes of death were respiratory disease (38%), CNS injury (30%) and infection (12%). Among the infants who died with WWLST, CNS injury was the main cause of death (47%), whereas respiratory disease (56%) and infection (20%) were the main causes in case of death without WWLST. Half (51%) of all deaths occurred within the first 7 days of life, and 35% occurred within 8 and 28 days.

CONCLUSION

The death of extremely preterm infants in NICU is a complex phenomenon in which the circumstances and causes of death are intertwined.

Early Life Factors Influencing Children Gut Microbiota at 3.5 Years from Two French Birth Cohorts

Early life gut microbiota-influencing factors may play an important role in programming individuals long-term health and substantial efforts have been devoted into studying the development of the gut microbiota in relation to early life events. This study aimed to examine in a single study, the persistence of associations between 20 factors occurring in the early life and the gut microbiota at 3.5 years of 798 children from two French nationwide birth cohorts, EPIPAGE 2 (very preterm children) and ELFE (late preterm and full-term children). Gut microbiota profiling was assessed using 16S rRNA gene sequencing-based method. Upon thorough adjustment of confounding factors, we demonstrated that gestational age was one of the factors most associated with gut microbiota differences with a noticeable imprint of prematurity at 3.5 years of age. Children born by cesarean section harbored lower richness and diversity and a different overall gut microbiota composition independently of preterm status. Children who had ever received human milk were associated with a Prevotella-driven enterotype (P_type) compared to those who had never received human milk. Living with a sibling was associated with higher diversity. Children with siblings and those attending daycare centers were associated with a P_type enterotype. Maternal factors including the country of birth and preconception maternal body mass index were associated with some microbiota characteristics: children born to overweight or obese mothers showed increased gut microbiota richness. This study reveals that multiple exposures operating from early life imprint the gut microbiota at 3.5 years that is a pivotal age when the gut microbiota acquires many of its adult characteristics.

Precision medicine via the integration of phenotype-genotype information in neonatal genome project

The explosion of next-generation sequencing (NGS) has enabled the widespread use of genomic data in precision medicine. Currently, several neonatal genome projects have emerged to explore the advantages of NGS to diagnose or screen for rare genetic disorders. These projects have made remarkable achievements, but still the genome data could be further explored with the assistance of phenotype collection. In contrast, longitudinal birth cohorts are great examples to record and apply phenotypic information in clinical studies starting at the neonatal period, especially the trajectory analyses for health development or disease progression. It is obvious that efficient integration of genotype and phenotype benefits not only the clinical management of rare genetic disorders but also the risk assessment of complex diseases. Here, we first summarize the recent neonatal genome projects as well as some longitudinal birth cohorts. Then, we propose two simplified strategies by integrating genotypic and phenotypic information in precision medicine based on current studies. Finally, research collaborations, sociological issues, and future perspectives are discussed. How to maximize neonatal genomic information to benefit the pediatric population remains an area in need of more research and effort.

Maternal pre-pregnancy obesity and offspring hyperactivity-inattention symptoms at 5 years in preterm and term children: a multi-cohort analysis

The objective of this study was to determine the relationship between maternal pre-pregnancy body mass index (BMI) and child hyperactivity-inattention symptoms (HIS) at 5 years, including preterm and term-born children, and to determine whether this association varied with gestational age. Maternal pre-pregnancy BMI and offspring HIS were assessed in 10,898 participants born ≥ 33 weeks of gestation from the ELFE cohort and 2646 children born between 23 and 34 weeks from the EPIPAGE 2 cohort. Reported pre-pregnancy weight (kg) and measured height (m) were collected from mothers at inclusion and used to classify BMI (kg/m²). Child HIS were evaluated using the Strengths and Difficulties Questionnaire around 5 years of age. Logistic regression estimated odds ratios (OR) of a high HIS score (≥ 90th percentile) in the ELFE cohort and generalized estimated equations were used in EPIPAGE 2 to account for non-independence of multiple births. As a negative control, paternal BMI was also considered as an exposure of interest in sensitivity analyses. Maternal pre-pregnancy obesity and overweight were associated with child HIS at 5 years in ELFE (adjusted OR [aOR] for obesity 1.27 [1.06, 1.53]; overweight aOR 1.16 [1.00, 1.36]) and pre-pregnancy obesity was associated with high HIS scores in preterm infants of EPIPAGE 2 (aOR 1.48 [1.06, 2.08]). In ELFE, the magnitude of the association increased with decreasing gestational age (interaction p = 0.02). High maternal pre-pregnancy BMI is associated with greater likelihood of high HIS scores in both at-term and preterm children at 5 years of age.

Very Preterm Children Gut Microbiota Comparison at the Neonatal Period of 1 Month and 3.5 Years of Life

Prematurity is a risk factor for dysbiosis of the gut microbiota due to particular birth conditions and frequent prolonged hospitalization of neonates. Although gut microbiota colonization after birth and its establishment during the hospitalization period have been studied in preterm infants, data on gut microbiota following discharge, particularly during early childhood, are scarce. The present study investigated the relationship between gut microbiota at 1 month after birth (hospitalization period) and 3.5 years of age in 159 preterm children belonging to the French EPIFLORE prospective observational cohort study. Analysis using bacterial 16S rRNA gene sequencing showed that the gut microbiota of preterm neonates at 1 month was highly variable and characterized by six distinct enterotypes. In contrast, the gut microbiota of the same children at 3.5 years of age showed less variability, with only two discrete enterotypes. An absence of association between enterotypes at 1 month and 3.5 years of age was observed. While the alpha diversity of gut microbiota significantly increased between 1 month and 3.5 years of age, for both alpha and beta diversities, there was no correlation between the 1-month and 3.5-years time points. Comparison at 3.5 years between children born either preterm (n = 159) or full-term (n = 200) showed no differences in terms of enterotypes, but preterm children harbored a lower Shannon diversity index and a different overall composition of microbiota than full-term children. This study suggests that the characteristics of the early gut microbiota of preterm children are not predictive of the microbial community composition at 3.5 years of age. However, the impact of gestational age is still noticeable on the gut microbiota up to 3.5 years of age.

Neurodevelopment at 5 years of age for preterm-born children according to mode of conception: a cohort study

BACKGROUND

Preterm delivery is a risk factor for sub-optimal neurodevelopment. Pregnancies conceived after medically-assisted reproduction - which includes in vitro fertilisation, with or without intracytoplasmic insemination, as well as induction of ovulation followed by intra-uterine insemination or timed intercourse - have a higher risk of preterm delivery. Few studies have evaluated the outcome at more than 2 years of age of such preterm-born children.

OBJECTIVE

To evaluate neurodevelopmental outcome at 5 ½ years of age of children born preterm according to the mode of conception (spontaneous versus medically-assisted reproduction).

STUDY DESIGN

4349 children born between 24 and 34 weeks of gestation who survived to 5 ½ years of age in the 2011 French prospective national cohort study EPIPAGE-2 were included: 814 in the medically-assisted reproduction group (433 by in vitro fertilisation, with or without intracytoplasmic insemination, and 381 by induction of ovulation) and 3535 in the spontaneously conceived group. Neurodevelopmental outcomes studied were sensory (hearing and vision) impairments, cerebral palsy, cognition and developmental coordination disorders. Multivariate analyses were performed with generalised estimating equation models adjusted for gestational age, antenatal steroids and social characteristics. All analyses were performed following multiple imputation. Sensitivity analyses were performed with the populations of singletons and cases with complete data.

RESULTS

No differences in cerebral palsy (adjusted odds ratio =1.00, 95% confidence interval 0.67-1.49), neurodevelopmental impairment (adjusted odds ratio=1.09; 95% confidence interval 0.82-1.45), or developmental coordination disorders (adjusted odds ratio=0.75; 95% confidence interval 0.50-1.12) were found between children born following medically-assisted reproduction and children born following spontaneous conception after adjustment for sociodemographic factors. For proportions of children with an intelligence quotient below one and two standard deviations, there were no differences between those born after medically-assisted reproduction or spontaneous pregnancy (respectively, adjusted odds ratio= 0.99 95% confidence interval 0.80-1.23, and adjusted odds ratio=1.14; 95% confidence interval 0.83-1.56). In subgroup analyses, no differences were seen between children born following induction of ovulation nor among those conceived through in vitro fertilisation when compared to children conceived spontaneously. Sensitivity analyses were consistent with the main results.

CONCLUSION

In this cohort of preterm born children, there was no evidence of an impact of the mode of conception on neurodevelopmental outcomes at 5 ½ years of age.

Ophthalmological Impairments at Five and a Half Years after Preterm Birth: EPIPAGE-2 Cohort Study

We report the 51/2 year prevalence of visual and oculomotor impairments in preterm children born at 24−34 weeks’ gestation (WG) using the population-based cohort study EPIPAGE-2, set in France, 2011. The main outcomes were imputed prevalence of refractive errors (REs), strabismus, and binocular visual acuity (VA). Children were clinically assessed by specially trained pediatricians. The population was also analyzed in terms of cerebral palsy at 51/2 years (no CP, stage 1, stage 2, or stage 3−5) and retinopathy of prematurity in the neonatal period (no ROP, stage 1 or 2, or severe ROP). Among the 4441 children included, 2718 (weighted percentage 58.7%) were clinically assessed. REs were reported in 43.1% (95% confidence interval 37.6−48.4), 35.2% (32.7−37.6), and 28.4% (25.0−31.8) of children born at 24−26, 27−31, and 32−34 WG (p < 0.01), respectively; strabismus rates were 19.5% (14.6−24.4), 14.8% (12.9−16.7), and 8.3% (6.2−10.4) (p < 0.001), respectively. Moderate/severe visual deficiencies (VA < 3.2/10) were present in 1.7% (0.2−3.3) of children born at 24−26 WG, and in less than 1% in other groups. A suboptimal VA 5/10−6.3/10 was measured in 40.6% (35.3−45.8) of children born at 24−26 WG, 35.8% (33.5−38.1) at 27−31 WG, and 33.7% (30.4−37.0) at 32−34 WG. CP and ROP were associated with strabismus and RE. The association between CP and VA was strong, while it was not observed for ROP. In this large cohort of preterm-born children, we found a high prevalence of RE and strabismus regardless of WG, supporting the need for specific attention in this population. High prevalence of suboptimal VA could be challenging for these children at the age of reading and writing acquisition.

Early Antibiotic Exposure and Adverse Outcomes in Very Preterm Infants at Low Risk of Early-Onset Sepsis: The EPIPAGE-2 Cohort Study

OBJECTIVE

To assess the association between early empirical antibiotics and neonatal adverse outcomes in very preterm infants without risk factors for early-onset sepsis (EOS).

STUDY DESIGN

This is a secondary analysis of the EPIPAGE-2 study, a prospective national population-based cohort that included all liveborn infants at 22-31 completed weeks of gestation in France in 2011. Infants at high risk of EOS (ie, born after preterm labor or preterm premature rupture of membranes or from a mother who had clinical chorioamnionitis or had received antibiotics during the last 72 hours) were excluded. Early antibiotic exposure was defined as antibiotic therapy started at day 0 or day 1 of life, irrespective of the duration and type of antibiotics. We compared treated and untreated patients using inverse probability of treatment weighting based on estimated propensity scores.

RESULTS

Among 648 very preterm infants at low risk of EOS, 173 (26.2%) had received early antibiotic treatment. Early antibiotic exposure was not associated with death or late-onset sepsis or necrotizing enterocolitis (OR, 1.04; 95% CI, 0.72-1.50); however, it was associated with higher odds of severe cerebral lesions (OR, 2.71; 95% CI, 1.25-5.86) and moderate-severe bronchopulmonary dysplasia (BPD) (OR, 2.30; 95% CI, 1.21-4.38).

CONCLUSIONS

Early empirical antibiotic therapy administrated in very preterm infants at low risk of EOS was associated with a higher risk of severe cerebral lesions and moderate-severe BPD.

Risk Factors for High-Arched Palate and Posterior Crossbite at the Age of 5 in Children Born Very Preterm: EPIPAGE-2 Cohort Study

INTRODUCTION

Children born very preterm have an immature sucking reflex at birth and are exposed to neonatal care that can impede proper palate growth.

OBJECTIVES

We aimed to describe the frequency of high-arched palate and posterior crossbite at the age of 5 in children born very preterm and to identify their respective risk factors.

METHODS

Our study was based on the data from EPIPAGE-2, a French national prospective cohort study, and included 2,594 children born between 24- and 31-week gestation. Outcomes were high-arched palate and posterior crossbite. Multivariable models estimated by generalized estimation equations with multiple imputation were used to study the association between the potential risk factors studied and each outcome.

RESULTS

Overall, 8% of children born very preterm had a high-arched palate and 15% posterior crossbite. The odds of high-arched palate were increased for children with low gestational age (24-29 vs. 30-31 weeks of gestation) [adjusted odds ratio (aOR) 1.76, 95% confidence interval (CI) 1.17, 2.66], thumb-sucking habits at the age of 2 (aOR 1.53, 95% CI 1.03, 2.28), and cerebral palsy (aOR 2.18, 95% CI 1.28, 3.69). The odds of posterior crossbite were increased for children with pacifier-sucking habits at the age of 2 (aOR 1.75, 95% CI 1.30, 2.36).

CONCLUSIONS

Among very preterm children, low gestational age and cerebral palsy are the specific risk factors for a high-arched palate. High-arched palate and posterior crossbite share non-nutritive sucking habits as a common risk factor. The oro-facial growth of these children should be monitored.

Antibiotic prophylaxis in preterm premature rupture of membranes at 24-31 weeks' gestation: perinatal and 2-year outcomes in the EPIPAGE-2 cohort

Objective

To compare different antibiotic prophylaxis administered after preterm premature rupture of membranes to determine whether any were associated with differences in obstetric and/or neonatal outcomes and/or neurodevelopmental outcomes at 2 years of corrected age.

Design

Prospective, nationwide, population‐based EPIPAGE‐2 cohort study of preterm infants.

Setting

France, 2011.

Sample

We included 492 women with a singleton pregnancy and a diagnosis of preterm premature rupture of membranes at 24–31 weeks. Exclusion criteria were contraindication to expectant management or indication for antibiotic therapy other than preterm premature rupture of membranes. Antibiotic prophylaxis was categorised as amoxicillin (n = 345), macrolide (n = 30), third‐generation cephalosporin (n = 45) or any combinations covering Streptococcus agalactiae and >90% of Escherichia coli (n = 72), initiated within 24 hours after preterm premature rupture of membranes.

Methods

Population‐averaged robust Poisson models.

Main Outcome Measures

Survival at discharge without severe neonatal morbidity, 2‐year neurodevelopment.

Results

With amoxicillin, macrolide, third‐generation cephalosporin and combinations, 78.5%, 83.9%, 93.6% and 86.0% of neonates were discharged alive without severe morbidity. The administration of third‐generation cephalosporin or any E. coli‐targeting combinations was associated with improved survival without severe morbidity (adjusted risk ratio 1.25 [95% confidence interval 1.08–1.45] and 1.10 [95 % confidence interval 1.01–1.20], respectively) compared with amoxicillin. We evidenced no increase in neonatal sepsis related to third‐generation cephalosporin‐resistant pathogen.

Conclusion

In preterm premature rupture of membranes at 24–31 weeks, antibiotic prophylaxis based on third‐generation cephalosporin may be associated with improved survival without severe neonatal morbidity when compared with amoxicillin, with no evidence of increase in neonatal sepsis related to third‐generation cephalosporin‐resistant pathogen.

Tweetable Abstract

Antibiotic prophylaxis after PPROM at 24–31 weeks: 3rd‐generation cephalosporins associated with improved neonatal outcomes.

Antibiotic prophylaxis after PPROM at 24–31 weeks: 3rd‐generation cephalosporins associated with improved neonatal outcomes.

Tocolysis in the management of preterm prelabor rupture of membranes at 22-33 weeks of gestation: study protocol for a multicenter, double-blind, randomized controlled trial comparing nifedipine with placebo (TOCOPROM)

Background

Preterm prelabor rupture of membranes (PPROM) before 34 weeks of gestation complicates 1% of pregnancies and accounts for one-third of preterm births. International guidelines recommend expectant management, along with antenatal steroids before 34 weeks and antibiotics. Up-to-date evidence about the risks and benefits of administering tocolysis after PPROM, however, is lacking. In theory, reducing uterine contractility could delay delivery and reduce the risks of prematurity and its adverse short- and long-term consequences, but it might also prolong fetal exposure to inflammation, infection, and acute obstetric complications, potentially associated with neonatal death or long-term sequelae. The primary objective of this study is to assess whether short-term (48 h) tocolysis reduces perinatal mortality/morbidity in PPROM at 22 to 33 completed weeks of gestation.

Methods

A randomized, double-blind, placebo-controlled, superiority trial will be performed in 29 French maternity units. Women with PPROM between 22^0/7 and 33^6/7 weeks of gestation, a singleton pregnancy, and no condition contraindicating expectant management will be randomized to receive a 48-hour oral treatment by either nifedipine or placebo (1:1 ratio). The primary outcome will be the occurrence of perinatal mortality/morbidity, a composite outcome including fetal death, neonatal death, or severe neonatal morbidity before discharge. If we assume an alpha-risk of 0.05 and beta-risk of 0.20 (i.e., a statistical power of 80%), 702 women (351 per arm) are required to show a reduction of the primary endpoint from 35% (placebo group) to 25% (nifedipine group). We plan to increase the required number of subjects by 20%, to replace any patients who leave the study early. The total number of subjects required is thus 850. Data will be analyzed by the intention-to-treat principle.

Discussion

This trial will inform practices and policies worldwide. Optimized prenatal management to improve the prognosis of infants born preterm could benefit about 50,000 women in the European Union and 40,000 in the United States each year.

Trial registration

ClinicalTrials.gov identifier: NCT03976063 (registration date June 5, 2019).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04047-2.