Cortical growth from infancy to adolescence in preterm and term-born children.

Early life experiences can exert a significant influence on cortical and cognitive development. Very preterm birth exposes infants to several adverse environmental factors during hospital admission, which affect cortical architecture. However, the subsequent consequence of very preterm birth on cortical growth from infancy to adolescence has never been defined; despite knowledge of critical periods during childhood for establishment of cortical networks. Our aims were to: chart typical longitudinal cortical development and sex differences in cortical development from birth to adolescence in healthy term-born children; estimate differences in cortical development between children born at term and very preterm; and estimate differences in cortical development between children with normal and impaired cognition in adolescence. This longitudinal cohort study included children born at term (≥37 weeks' gestation) and very preterm (<30 weeks' gestation) with MRI scans at ages 0, 7 and 13 years (n = 66 term-born participants comprising 34 with one scan, 18 with two scans and 14 with three scans; n = 201 very preterm participants comprising 56 with one scan, 88 with two scans and 57 with three scans). Cognitive assessments were performed at age 13 years. Cortical surface reconstruction and parcellation were performed with state-of-the-art, equivalent MRI analysis pipelines for all time points, resulting in longitudinal cortical volume, surface area and thickness measurements for 62 cortical regions. Developmental trajectories for each region were modelled in term-born children, contrasted between children born at term and very preterm, and contrasted between all children with normal and impaired cognition. In typically developing term-born children, we documented anticipated patterns of rapidly increasing cortical volume, area and thickness in early childhood, followed by more subtle changes in later childhood, with smaller cortical size in females than males. In contrast, children born very preterm exhibited increasingly reduced cortical volumes, relative to term-born children, particularly during ages 0-7 years in temporal cortical regions. This reduction in cortical volume in children born very preterm was largely driven by increasingly reduced cortical thickness rather than area. This resulted in amplified cortical volume and thickness reductions by age 13 years in individuals born very preterm. Alterations in cortical thickness development were found in children with impaired language and memory. This study shows that the neurobiological impact of very preterm birth on cortical growth is amplified from infancy to adolescence. These data further inform the long-lasting impact on cortical development from very preterm birth, providing broader insights into neurodevelopmental consequences of early life experiences.

Association of Growth During Infancy with Neurodevelopment and Obesity in Children Born Very Preterm: The Environmental Influences on Child Health Outcomes Cohort.

OBJECTIVE: To evaluate associations between change in weight z score after neonatal intensive care unit (NICU) discharge and neurodevelopmental outcomes and obesity at 12-48 months of age among individuals born very preterm. STUDY DESIGN: This secondary analysis used data from infants born very preterm participating in the Environmental influences on Child Health Outcomes cohort (n = 1400). Growth during infancy was calculated as change in weight z score between NICU discharge and follow-up at a mean of 27 months of age. Very low weight gain was defined as a change in weight z score <-1.67; very high weight gain was a change in weight z score >1.67. Neurodevelopmental outcomes included the Bayley Scales of Infant and Toddler Development, Child Behavior Checklist 1.5-5 years, and Modified Checklist for Autism in Toddlers. Multivariable linear regression was used to estimate associations between increase in weight z score and neurodevelopmental outcomes. RESULTS: Very low weight gain between NICU discharge and follow-up (experienced by 6.4% of participants) was associated with lower scores on cognitive (adjusted mean difference: -4.26; 95% CI: -8.55, -0.04) and language (adjusted mean difference: -4.80; 95% CI: -9.70, -0.11) assessments. Very high weight gain (experienced by 13.6% of participants) was associated with an increased obesity risk (adjusted relative risk: 6.20; 95% CI: 3.99, 9.66) but not with neurodevelopmental outcomes. CONCLUSIONS: Very high weight gain in the first 12-48 months after NICU discharge was associated with a higher risk of obesity at follow-up; very low weight gain was associated with lower scores on cognitive and language assessments.

Cesarean delivery is associated with lower neonatal mortality among breech pregnancies: a systematic review and meta-analysis of preterm deliveries ≤32 weeks of gestation.

OBJECTIVE: To investigate the association between actual and planned modes of delivery, neonatal mortality, and short-term outcomes among preterm pregnancies ≤32 weeks of gestation. DATA SOURCES: A systematic literature search was conducted in 3 main databases (PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to November 16, 2022. The protocol was registered in advance in the International Prospective Register of Systematic Reviews (CRD42022377870). STUDY ELIGIBILITY CRITERIA: Eligible studies examined pregnancies ≤32nd gestational week. All infants received active care, and the outcomes were reported separately by different modes of delivery. Singleton and twin pregnancies at vertex and breech presentations were included. Studies that included pregnancies complicated with preeclampsia and abruptio placentae were excluded. Primary outcomes were neonatal mortality and intraventricular hemorrhage. STUDY APPRAISAL AND SYNTHESIS METHODS: Articles were selected by title, abstract, and full text, and disagreements were resolved by consensus. Random effects model-based odds ratios with corresponding 95% confidence intervals were calculated for dichotomous outcomes. Risk Of Bias In Non-randomized Studies - of Interventions-I was used to assess the risk of bias. RESULTS: A total of 19 observational studies were included involving a total of 16,042 preterm infants in this systematic review and meta-analysis. Actual cesarean delivery improves survival (odds ratio, 0.62; 95% confidence interval, 0.42-0.9) and decreases the incidence of intraventricular hemorrhage (odds ratio, 0.70; confidence interval, 0.57-0.85) compared to vaginal delivery. Planned cesarean delivery does not improve the survival of very and extremely preterm infants compared to vaginal delivery (odds ratio, 0.87; 95% confidence interval, 0.53-1.44). Subset analysis found significantly lower odds of death for singleton breech preterm deliveries born by both planned (odds ratio, 0.56; 95% confidence interval, 0.32-0.98) and actual (odds ratio, 0.34; 95% confidence interval, 0.13-0.88) cesarean delivery. CONCLUSION: Cesarean delivery should be the mode of delivery for preterm ≤32 weeks of gestation breech births due to the higher mortality in preterm infants born via vaginal delivery.

Association between risk of preterm birth and long-term and short-term exposure to ambient carbon monoxide during pregnancy in chongqing, China: a study from 2016-2020.

BACKGROUND: Preterm birth (PTB) is an important predictor of perinatal morbidity and mortality. Previous researches have reported a correlation between air pollution and an increased risk of preterm birth. However, the specific relationship between short-term and long-term exposure to carbon monoxide (CO) and preterm birth remains less explored. METHODS: A population-based study was conducted among 515,498 pregnant women in Chongqing, China, to assess short-term and long-term effects of CO on preterm and very preterm births. Generalized additive models (GAM) were applied to evaluate short-term effects, and exposure-response correlation curves were plotted after adjusting for confounding factors. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using COX proportional hazard models to estimate the long-term effect. RESULTS: The daily incidence of preterm and very preterm birth was 5.99% and 0.41%, respectively. A positive association between a 100 µg/m³ increase in CO and PTB was observed at lag 0-3 days and 12-21 days, with a maximum relative risk (RR) of 1.021(95%CI: 1.001-1.043). The exposure-response curves (lag 0 day) revealed a rapid increase in PTB due to CO. Regarding long-term exposure, positive associations were found between a 100 µg/m3 CO increase for each trimester(Model 2 for trimester 1: HR = 1.054, 95%CI: 1.048-1.060; Model 2 for trimester 2: HR = 1.066, 95%CI: 1.060-1.073; Model 2 for trimester 3: HR = 1.007, 95%CI: 1.001-1.013; Model 2 for entire pregnancy: HR = 1.080, 95%CI: 1.073-1.088) and higher HRs of very preterm birth. Multiplicative interactions between air pollution and CO on the risk of preterm and very preterm birth were detected (P- interaction<0.05). CONCLUSIONS: Our findings suggest that short-term exposure to low levels of CO may have protective effects against preterm birth, while long-term exposure to low concentrations of CO may reduce the risk of both preterm and very preterm birth. Moreover, our study indicated that very preterm birth is more susceptible to the influence of long-term exposure to CO during pregnancy, with acute CO exposure exhibiting a greater impact on preterm birth. It is imperative for pregnant women to minimize exposure to ambient air pollutants.

The early educational environment at five years of age in a European cohort of children born very preterm: challenges and opportunities for research.

BACKGROUND: Early childhood education offers opportunities for stimulation in multiple developmental domains and its positive impact on long-term outcomes and wellbeing for children is well documented. Few studies have explored early education in children born very preterm (VPT; <32 weeks of gestation) who are at higher risk of neurodevelopmental disorders and poor educational outcomes than their term-born peers. The purpose of the study is to describe and compare the educational environment of children born VPT in European countries at 5 years of age according to the degree of perinatal risk. METHODS: Data originated from the population-based Screening to Improve Health In very Preterm infants (SHIPS) cohort of children born VPT in 2011/2012 in 19 regions from 11 European countries. Perinatal data were collected from medical records and the 5-year follow-up was conducted using parental questionnaires. Outcomes at 5 years were participation in early education (any, type, intensity of participation) and receipt of special educational support, which were harmonized across countries. RESULTS: Out of 6,759 eligible children, 3,687 (54.6%) were followed up at 5 years (mean gestational age 29.3 weeks). At 5 years, almost all children (98.6%) were in an educational program, but type (preschool/primary), attendance (full-time/part-time) and use and type of school support/services differed by country. In some countries, children with high perinatal risk were more likely to be in full-time education than those with low risk (e.g. Estonia: 97.9% vs. 87.1%), while the inverse pattern was observed elsewhere (e.g. Poland: 78.5% vs. 92.8%). Overall, 22.8% of children received special educational support (country range: 12.4-34.4%) with more support received by children with higher perinatal risk. Large variations between countries remained after adjustment for socio-demographic characteristics. CONCLUSIONS: There are marked variations in approaches to early education for children born VPT in Europe, raising opportunities to explore its impact on their neurodevelopment and well-being.

Associations between the aetiology of preterm birth and mortality and neurodevelopment up to 11 years.

AIM: To investigate how the aetiology of very preterm birth/very low birth weight is associated with mortality and later neurodevelopmental outcomes. METHODS: Very preterm/very low-birth weight singletons were categorised based on the aetiology of preterm birth: spontaneous preterm birth (n = 47, 28.1%), preterm premature rupture of membranes (n = 56, 33.5%) or placental vascular pathology (n = 64, 38.3%). Mortality, cerebral palsy, severe cognitive impairment by 11 years of age (<2SD) and mean full-scale intelligence quotient at 11 years were studied in association with birth aetiology. RESULTS: There was no difference in mortality or rate of cerebral palsy according to birth aetiologies. The rate of severe cognitive impairment was lower (4.9% vs. 15.3%) in the preterm premature rupture of the membrane group in comparison to the placental vascular pathology group (OR 0.2, 95% CI 0.03-0.9, adjusted for gestational age). At 11 years, there was no statistically significant difference in the mean full-scale intelligence quotient. CONCLUSION: Placental vascular pathology, as the aetiology of very preterm birth/very low birth weight, is associated with a higher rate of severe cognitive impairments in comparison to preterm premature rupture of membranes, although there was no difference in the mean full-scale intelligence quotient at 11 years. The aetiology of very preterm birth/very low birth weight was not associated with mortality or the rate of cerebral palsy.

Neurodevelopmental outcomes at 18 months of children diagnosed with CHD compared to children born very preterm.

OBJECTIVE: To compare neurodevelopmental outcomes and parent behaviour ratings of children born term with CHD to children born very preterm. METHODS: A clinical research sample of 181 children (CHD [n = 81]; very preterm [≤32 weeks; n = 100]) was assessed at 18 months. RESULTS: Children with CHD and born very preterm did not differ on Bayley-III cognitive, language, or motor composite scores, or on expressive or receptive language, or on fine motor scaled scores. Children with CHD had lower ross motor scaled scores compared to children born very preterm (p = 0.047). More children with CHD had impaired scores (<70 SS) on language composite (17%), expressive language (16%), and gross motor (14%) indices compared to children born very preterm (6%; 7%; 3%; ps < 0.05). No group differences were found on behaviours rated by parents on the Child Behaviour Checklist (1.5-5 years) or the proportion of children with scores above the clinical cutoff. English as a first language was associated with higher cognitive (p = 0.004) and language composite scores (p < 0.001). Lower median household income and English as a second language were associated with higher total behaviour problems (ps < 0.05). CONCLUSIONS: Children with CHD were more likely to display language and motor impairment compared to children born very preterm at 18 months. Outcomes were associated with language spoken in the home and household income.

Different pathways for preterm birth between singleton and twin pregnancies: a population-based registry study of 481 176 nulliparous women.

OBJECTIVE: To explore the contribution of pregnancy-related complications on the prevalence of extremely, very and late preterm births in singleton and twin pregnancies. To study the risk of spontaneous preterm birth in twin pregnancies compared with singleton pregnancies. DESIGN: Population-based registry study. SETTING: Medical birth registry of Norway and Statistics Norway. POPULATION: Nulliparous women with singleton (n = 472 449) or twin (n = 8727) births during 1999-2018. METHODS: Prevalence rates of pregnancy-related complications for extremely, very and late preterm birth in twin and singleton pregnancies were calculated with 95% confidence intervals. Multivariable logistic regression was applied to assess odds ratios for preterm birth, adjusted for obstetric and socio-economic factors. MAIN OUTCOME MEASURES: Extremely preterm (<28+0  weeks of gestation), very preterm (28+0 -33+6  weeks of gestation) and late preterm (34+0 -36+6  weeks of geatation) birth. RESULTS: Preterm birth was significantly more prevalent in twin pregnancies than in singleton pregnancies in all categories: all preterm (54.7% vs 6.1%), extremely preterm (3.6% vs 0.4%), very preterm (18.2% vs 1.4%) and late preterm (33.0% vs 4.3%) births. Stillbirth, congenital malformation and pre-eclampsia were more prevalent in twin pregnancies than in singleton pregnancies, but the prevalence of complications differed in the three categories of preterm birth. Pre-eclampsia was more prevalent in singleton than in twin pregnancies ending in extremely and very preterm birth. The adjusted odds of spontaneous preterm live birth were between 19- and 54-fold greater in twin pregnancies than in singleton pregnancies. CONCLUSIONS: Singleton and twin pregnancies seem to have different pathways leading to extremely, very and late preterm birth.

Comparative evaluation of the health utilities index mark 3 and the short form 6D: evidence from an individual participant data meta-analysis of very preterm and very low birthweight adults.

BACKGROUND: The most appropriate preference-based health-related quality of life (HRQoL) instruments for trials or research studies that ascertain the consequences of individuals born very preterm and/or low birthweight (VP/VLBW) are not known. Agreement between the HUI3 and SF-6D multi-attribute utility measures have not been previously investigated for VP/VLBW and normal birthweight or term-born controls. This study examined the agreement between the outputs of the HUI3 and SF-6D measures among adults born VP/VLBW and normal birthweight or term born controls. METHODS: We used two prospective cohorts of individuals born VP/VLBW and controls contributing to the 'Research on European Children and Adults Born Preterm' (RECAP) consortium which assessed HRQoL using two preference-based measures. The combined dataset of individual participant data (IPD) included 407 adult VP/VLBW survivors and 367 controls, ranging in age from 18 to 26 years. Bland-Altman plots, intra-class correlation coefficients, and generalized linear mixed models in a one-step approach were used to examine agreement between the measures. RESULTS: There was significant discordance between the HUI3 and SF-6D multi-attribute utility measures in the VP/VLBW sample, controls, and in the combined samples. Agreement between the HUI3 and SF-6D multi-attribute utility measures was weaker in controls compared with VP/VLBW individuals. CONCLUSIONS AND RELEVANCE: The HUI3 and SF-6D each provide unique information on different aspects of health status across the groups. The HUI3 better captures preterm-related changes to HRQoL in adulthood compared to SF-6D. Studies focused on measuring physical or cognitive aspects of health will likely benefit from using the HUI3 instead of the SF-6D, regardless of gestational age at birth and birthweight status.

Perinatal characteristics and neonatal outcomes of singletons and twins in Chinese very preterm infants: a cohort study.

BACKGROUND: The prevalence of preterm birth has been rising, and there is a paucity of nationwide data on the perinatal characteristics and neonatal outcomes of twin deliveries of very preterm infants (VPIs) in China. This study compared the perinatal characteristics and outcomes of singletons and twins admitted to neonatal intensive care units (NICUs) in China. METHODS: The study population comprised all infants born before 32 weeks in the Chinese Neonatal Network (CHNN) between January 2019 and December 2019. Three-level and population-average generalized estimating equation (GEE)/alternating logistic regression (ALR) models were used to determine the association of twins with neonatal morbidities and the use of NICU resources. RESULTS: During the study period, there were 6634 (71.2%) singletons and 2680 (28.8%) twins, with mean birth weights of 1333.70 g and 1294.63 g, respectively. Twins were significantly more likely to be delivered by caesarean section (p < 0.01), have antenatal steroid usage (p = 0.048), have been conceived by assisted reproductive technology (ART) (p < 0.01), have a higher prevalence of maternal diabetes (p < 0.01) and be inborn (p < 0.01) than singletons. In addition, twins had a lower prevalence of small for gestational age, maternal hypertension, and primigravida mothers than singletons (all p < 0.01). After adjusting for potential confounders, twins had higher mortality rates (adjusted odds ratio [AOR] 1.28, 95% confidence interval [CI] 1.10-1.49), higher incidences of short-term composite outcomes (AOR 1.28, 95% CI 1.09-1.50), respiratory distress syndrome (RDS) (AOR 1.30, 95% CI 1.12-1.50), and bronchopulmonary dysplasia (BPD) (AOR 1.10, 95% CI 1.01-1.21), more surfactant usage (AOR 1.22, 95% CI 1.05-1.41) and prolonged hospital stays (adjusted mean ratio 1.03, 95% CI 1.00-1.06), compared to singletons. CONCLUSION: Our work suggests that twins have a greater risk of mortality, a higher incidence of RDS and BPD, more surfactant usage, and longer NICU stays than singletons among VPIs in China.

Cross-modal coherence and incoherence of early infant interactive behavior: links to attachment in infants born very preterm or full-term.

Infants exhibit flexibly organized configurations of facial, vocal, affective, and motor behavior during caregiver-infant interactions that convey convergent messages about their internal states and desires. Prior work documents that greater cross-modal discrepancy at 4 months predicts disorganized attachment. Here, we evaluated whether: very preterm (VPT) or full-term (FT) status predicts cross-modal coherence or incoherence in infants' behavior with the caregiver at 3 months; and, regardless of prematurity, whether cross-modal interactive coherence or incoherence predicts 12-month attachment. Participants included 155 infants (85 FT; 70 VPT), and their mothers followed from birth to 12 months (corrected age). Infants' cross-modal coherent and incoherent responses were scored microanalytically from videotaped en-face interactions. Infants' attachment security was evaluated during Ainsworth's Strange Situation. Infants born VPT exhibited more incoherent cross-modal responses and insecure attachment than infants born FT. Regardless of prematurity, infants' coherent and incoherent cross-modal interactive behaviors at 3 months predicted different attachment patterns at 12 months.

Ventricular Volume in Infants Born Very Preterm: Relationship with Brain Maturation and Neurodevelopment at Age 4.5 Years.

OBJECTIVE: To evaluate the relationship of quantitative ventricular volume with brain maturation and neurodevelopmental outcomes at age 4.5 years in children born very preterm. STUDY DESIGN: T1-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy were performed shortly after birth (n = 212) and at term-equivalent age (TEA) (n = 194). Intraventricular hemorrhage (IVH) grade and white matter injury (WMI) volume were measured on early T1-weighted magnetic resonance imaging (MRI) scans. Total cerebral volume and ventricular volume were quantified using the Multiple Automatically Generated Templates-Brain pipeline. At age 4.5 years, 178 children (84%) underwent cognitive and motor assessments. Multivariable linear regression was used to examine the relationships between ventricular volume and neurodevelopmental outcomes. Generalized estimating equations were used to account for repeated measures when analyzing neonatal MRI data. All models accounted for sex, postmenstrual age at scan, WMI volume, IVH grade, and total cerebral volume and were corrected for multiple comparisons. RESULTS: On early MRI, 97 infants had IVH (grade 1, n = 22; grade 2, n = 66; grade 3, n = 9), and 68 had WMI (median, 44 mm3; IQR, 21-296 mm3). IQ at 4.5 years was associated with MRI ventricular volume at the early (ß = -0.64; P < .001) and TEA (ß = -0.44, P < .001) time points. Motor outcomes were associated with ventricular volume at TEA (ß = -0.84, P = .01). Greater ventricular volume independently predicted lower fractional anisotropy in corpus callosum (genu: ß = -0.0008, P = .002; splenium: ß = -0.003, P < .001) and optic radiations (ß = -0.001, P = .004); ventricular volume did not predict the N-acetylaspartate/choline ratio. CONCLUSIONS: In children born very preterm, neonatal ventricular size was associated with 4.5-year neurodevelopmental outcomes. Our findings suggest that white matter maturation may be abnormal in the setting of enlarged ventricular size beyond that expected from concurrent brain injuries.

Development of a data classification system for preterm birth cohort studies: the RECAP Preterm project.

BACKGROUND: The small sample sizes available within many very preterm (VPT) longitudinal birth cohort studies mean that it is often necessary to combine and harmonise data from individual studies to increase statistical power, especially for studying rare outcomes. Curating and mapping data is a vital first step in the process of data harmonisation. To facilitate data mapping and harmonisation across VPT birth cohort studies, we developed a custom classification system as part of the Research on European Children and Adults born Preterm (RECAP Preterm) project in order to increase the scope and generalisability of research and the evaluation of outcomes across the lifespan for individuals born VPT. METHODS: The multidisciplinary consortium of expert clinicians and researchers who made up the RECAP Preterm project participated in a four-phase consultation process via email questionnaire to develop a topic-specific classification system. Descriptive analyses were calculated after each questionnaire round to provide pre- and post- ratings to assess levels of agreement with the classification system as it developed. Amendments and refinements were made to the classification system after each round. RESULTS: Expert input from 23 clinicians and researchers from the RECAP Preterm project aided development of the classification system's topic content, refining it from 10 modules, 48 themes and 197 domains to 14 modules, 93 themes and 345 domains. Supplementary classifications for target, source, mode and instrument were also developed to capture additional variable-level information. Over 22,000 individual data variables relating to VPT birth outcomes have been mapped to the classification system to date to facilitate data harmonisation. This will continue to increase as retrospective data items are mapped and harmonised variables are created. CONCLUSIONS: This bespoke preterm birth classification system is a fundamental component of the RECAP Preterm project's web-based interactive platform. It is freely available for use worldwide by those interested in research into the long term impact of VPT birth. It can also be used to inform the development of future cohort studies.

Early factors associated with risk of developmental coordination disorder in very preterm children: A prospective area-based cohort study in Italy.

BACKGROUND: Developmental coordination disorder (DCD) is a motor disorder of unknown aetiology that may have long-term consequences on daily activities, and psychological and physical health. Studies investigating risk factors for DCD have so far provided inconsistent results. OBJECTIVES: To assess, using a parent-report screening tool, risk of DCD in school-age very preterm children born in Italy, and investigate the associated early biomedical and sociodemographic factors. METHODS: A prospective area-based cohort (804 children, response rate 73.4%) was assessed at 8-11 years of age in three Italian regions. Perinatal data were abstracted from medical records. DCD risk was measured using the Italian-validated version of the Developmental Coordination Disorder Questionnaire (DCDQ-IT). For this study, children with cognitive deficit (i.e. intelligence quotient <70), cerebral palsy, severe vision and hearing disabilities, and other impairments affecting movement were excluded. A total of 629 children were analysed. We used inverse probability weighting to account for loss to follow-up, and multilevel, multivariable modified Poisson models to obtain adjusted risk ratio (aRR) and 95% confidence interval (CI). Missing values in the covariates were imputed. RESULTS: 195 children (weighted proportion 31.8%, 95% CI 28.2, 35.6) scored positive on the DCDQ-IT, corresponding to the 15th centile of the reference Movement-ABC test. Factors associated with overall DCD risk were male sex (aRR 1.35, 95% CI 1.05, 1.73), intrauterine growth restriction (aRR 1.45, 95% CI 1.14, 1.85), retinopathy of prematurity (aRR 1.62, 95% CI 1.07, 2.45), and older maternal age at delivery (aRR 1.39, 95% CI 1.09, 1.77). Complete maternal milk feeding at discharge from the neonatal unit and higher parental socio-economic status were associated with decreased risk. CONCLUSIONS: Both biomedical and sociodemographic factors increase DCD risk. These findings can contribute to elucidating the origins of this disorder, and assist in the identification of children at risk for early referral and intervention.

Risk of preterm birth in relation to history of preterm birth: a population-based registry study of 213 335 women in Norway.

OBJECTIVE: To assess the association between preterm first birth and preterm second birth according to gestational age and to determine the role of placental disorder in recurrent preterm birth. DESIGN: Population-based registry study. SETTING: Medical Birth Registry of Norway and Statistics Norway. POPULATION: Women (n = 213 335) who gave birth to their first and second singleton child during 1999-2014 (total n = 426 670 births). METHODS: Multivariate logistic regression analyses, adjusted for placental disorders, maternal, obstetric and socio-economic factors. MAIN OUTCOME MEASURES: Extremely preterm (<28+0 weeks), very preterm (28+0 -33+6 weeks) and late preterm (34+0 -36+6 weeks) second birth. RESULTS: Preterm birth (<37 weeks) rates were 5.6% for first births and 3.7% for second births. Extremely preterm second births (0.2%) occurred most frequently among women with an extremely preterm first birth (aOR 12.90, 95% CI 7.47-22.29). Very preterm second births (0.7%) occurred most frequently after an extremely preterm birth (aOR 12.98, 95% CI 9.59-17.58). Late preterm second births (2.8%) occurred most frequently after a previous very preterm birth (aOR 6.86, 95% CI 6.11-7.70). Placental disorders contributed 30-40% of recurrent extremely and very preterm births and 10-20% of recurrent late preterm birth. CONCLUSION: A previous preterm first birth was a major risk factor for a preterm second birth. The contribution of placental disorders was more pronounced for recurrent extremely and very preterm birth than for recurrent late preterm birth. Among women with any category of preterm first birth, more than one in six also had a preterm second birth (17.4%). TWEETABLE ABSTRACT: Preterm first birth is a major risk factor for subsequent preterm birth, regardless of maternal, obstetric or fetal risk factors.

Analysis of risk factors related to extremely and very preterm birth: a retrospective study.

BACKGROUND: Preterm birth is one of the main causes of perinatal morbidity and mortality and imposes a heavy burden on families and society. The aim of this study was to identify risk factors and analyze birth conditions and complications of newborns born at < 32 gestational weeks for extremely preterm (EP) and very preterm (VP) birth in the clinic to further extend the gestational period. METHODS: We performed a retrospective cohort study and collected data from 1598 pregnant women and 1660 premature newborns (excluding 229 premature babies who died due to severe illness and abandonment) admitted to the Obstetrics and Gynecology Hospital Affiliated with Nanjing Medical University in China from 2016 to 2020. We compared women's and newborns' characteristics by t-tests and Chi-square tests for continuous and categorical variables, respectively. Multivariable logistic regression was performed to estimate the effects of risk factors on EP and VP birth. RESULTS: We identified 3 independent risk factors for EP birth: cervical incompetency (P < 0.001); multiple pregnancy (P < 0.01), primipara (P < 0.001). Additionally, we identified 4 independent risk factors for VP birth: gestational diabetes mellitus (GDM) (P < 0.05), preterm premature rupture of membrane (PPROM) (P < 0.01), fetal intrauterine distress (P < 0.001), and hypertensive disorder complicating pregnancy (HDCP) (P < 0.001). In addition, pairwise comparisons revealed statistically significant differences in the incidence rates of neonatal pneumonia, bronchopulmonary dysplasia (BPD) and sepsis between the 28-28 + 6 and 29-29 + 6 weeks of gestation groups (P < 0.05). Compared with 28-28 + 6 weeks of gestation, neonatal complications were significantly more common at < 26 weeks of gestation (P < 0.05). The incidence rates of neonatal intracranial hemorrhage(NICH), patent ductus arteriosus(PDA), patent foramen ovale(PFO), pneumonia, BPD and sepsis were significantly higher in the 26-26 + 6 and 27-27 + 6 gestational weeks than in the 28-28 + 6 gestational weeks (P < 0.05). CONCLUSION: PPROM, is the most common risk factor for EP and VP birth, and cervical insufficiency, multiple pregnancy, and primipara are independent risk factors for EP birth. Therefore, during pregnancy, attention should be devoted to the risk factors for PPROM, and reproductive tract infection should be actively prevented to reduce the occurrence of PPROM. Identifying the risk factors for cervical insufficiency, actively intervening before pregnancy, and cervical cervix ligation may be considered to reduce the occurrence of EP labor. For iatrogenic preterm birth, the advantages and disadvantages should be carefully weighed, and the gestational period should be extended beyond 28 weeks to enhance the safety of the mother and child and to improve the outcomes of preterm birth.

The experience of mothering a preterm: a prolonged crisis with the potential for personal growth.

OBJECTIVE AND BACKGROUND: The nine months of pregnancy allow mothers to plan for the birth of their child practically and emotionally. A very preterm birth, which is generally unexpected and requires the infant's stay in the Neonatal Intensive Care Unit (NICU), is perceived as a crisis by most mothers. This study sought to investigate the significance for the mother of the combined experience of a very preterm birth and the infant's stay in the NICU two-three years after the birth. METHODS: Using qualitative methodology, semi-structured in-depth interviews were conducted with 13 mothers (age 26-44) whose infants were born at 24-32 weeks. The analysis adopted the approach of multi-level listening to the diverse voices of the interviewees. RESULTS: Four core themes emerged: negative feelings about the preterm birth; the NICU experience as a crisis; long-term effects of the very preterm birth and NICU experience; personal growth following the preterm birth and NICU. DISCUSSION: In view of the findings, we discuss the meaning of the circumstances surrounding preterm birth on motherhood, and offer recommendations for practitioners.

Serotonin transporter gene methylation and emotional regulation in preschool children born preterm: A longitudinal evaluation of the role of negative emotionality in infancy.

The aim of the study was to assess the contribution of negative emotionality at 3 months (T1) and serotonin transporter gene (SLC6A4) DNA methylation at 4.5 years of age (T2) to emotion regulation in pre-schoolers born very preterm and full-term. Forty one children (n = 21 born very preterm, n = 20 born full-term) participated in the study. Fretful behavior was assessed at T1 in response to the Face-to-FaceStill-Face (FFSF) paradigm. At T2, SLC6A4 DNA methylation was analyzed and emotion regulation was assessed using an observational procedure (i.e., the Pre-schooler Regulation of Emotional Stress, PRES). The very preterm group displayed higher emotion dysregulation during the PRES Reactivity phase than the full-term group. Higher levels of fretful behavior at 3 months were associated with greater emotional distress only for very preterm children with higher methylation at T2. No significant associations emerged in the full-term group. Despite current findings cannot be generalized owing to the relatively small sample size, this work provides preliminary longitudinal evidence about the link between negative emotionality during infancy, stress-linked epigenetic status at 4.5 years and emotion dysregulation in preschoolers born preterm.

El propósito del estudio fue evaluar la contribución de la emocionalidad negativa a los 3 meses (T1) y la metilación del ADN en el gen transportador de la serotonina (SLC6A4) a los 4 años y medio de edad (T2) a la regulación de la emoción en prescolares nacidos muy antes de la gestación completa o de gestación completa. Cuarenta y un niños (n = 21 nacidos muy antes de la gestación completa, n = 20 nacidos de gestación completa) participaron en el estudio. El comportamiento irritable se evaluó a T1 como respuesta al Cara-a-Cara del paradigma de la Cara Inmóvil (FFSF). A T2, se analizó la metilación de ADN SLC6A4 y se evaluó la regulación de la emoción usando un procedimiento de observación (v.g. La Regulación del Estrés Emocional del Prescolar, PRES). El grupo nacido muy antes de la gestación completa mostró una más alta desregulación durante la fase de Reactividad PRES que el grupo nacido de gestación completa. Los niveles más altos de comportamiento irritable a los 3 meses se asociaron con una mayor angustia emocional solamente para los niños nacidos muy antes de la gestación completa con más alta metilación al T2. Ninguna asociación significativa surgió del grupo nacido de gestación completa. A pesar de que los actuales resultados no se pueden generalizar debido al tamaño relativamente pequeño del grupo muestra, este trabajo ofrece aporta evidencia longitudinal preliminar acerca de la conexión entre la emocionalidad negativa durante la infancia, el estado epigenético relacionado con el estrés a los 4 años y medio y la desregulación de la emoción en prescolares nacidos antes de la completa gestación.

Le but de cette étude était d'évaluer la contribution de l'émotivité négative à 3 mois (T1) et du gène vecteur de la sérotonine (SLC6A4) méthylation de l'ADN à l'âge de 4,5 ans (T2) à la régulation de l'émotion chez les enfants d'âge préscolaire nés très prématurés et à plein terme. Quarante et un enfant (n = 21 nés très prématurés, n = 20 nés à plein terme) ont participé à l'étude. Le comportement agité a été évalué au T1 en réponse au paradigme face-à-face visage inexpressif (abrégé FFSF en anglais). Au T2, la méthylation de l'ADN SLC6A4 a été analysée et la régulation de l'émotion a été évaluée en utilisant un protocole d'observation (à savoir, la Régulation du Stress Emotionnel de l'Enfant d'Age Préscolaire, abrégé en anglais PRES). Le groupe très prématuré a fait état d'une dysrégulation de l'émotion plus élevée durant la phase de Réactivité PRES que le groupe né à plein terme. Des niveaux plus élevés de comportement agité à 3 mois étaient liés à une détresse émotionnelle plus grande uniquement pour les enfants très prématurés avec une méthylation plus élevée au T2. Aucune association importante n'a émergé dans le groupe à plein terme. En dépit du fait que les résultats actuels ne peuvent pas être généralisés à cause de la taille relativement petite de l'échantillon, ce travail offre des preuves longitudinales préliminaires sur le lien entre l'émotivité négative durant la petite enfant, le statut épigénétique lié au stress à 4,5 ans et la dysrégulation de l'émotion chez les enfants d'âge préscolaires nés avant terme.

Risk factors for very preterm delivery out of a level III maternity unit: The EPIPAGE-2 cohort study.

BACKGROUND: Regionalisation programmes aim to ensure that very preterm infants are born in level III units (inborn) through antenatal referral or transfer. Despite widespread knowledge about better survival without disability for inborn babies, 10%-30% of women deliver outside these units (outborn). OBJECTIVE: To investigate risk factors associated with outborn deliveries and to estimate the proportion that were probably or possibly avoidable. METHODS: We used a national French population-based cohort including 2205 women who delivered between 24 and 30+6  weeks in 2011. We examined risk factors for outborn delivery related to medical complications, antenatal care, sociodemographic characteristics and living far from a level III unit using multivariable binomial regression. Avoidable outborn deliveries were defined by pregnancy risk (obstetric history, antenatal hospitalisation) and time available for transfer. RESULTS: 25.0% of women were initially booked in level III, 9.1% were referred, 49.8% were transferred, and 16.1% had outborn delivery. Risk factors for outborn delivery were gestational age <26 weeks (adjusted relative risk (aRR) 1.37, 95% confidence interval (CI) 1.13, 1.66), inadequate antenatal care (aRR 1.39, 95% CI 1.10, 1.81), placental abruption (aRR 1.66, 95% CI 1.27, 2.17), and increased distance to the closest level III unit ((aRR 2.79, 95% CI 2.00, 3.92) in the 4th versus 1st distance quartile). Among outborn deliveries, 16.7% were probably avoidable, and 25.6% possibly avoidable, which could increase the proportion of inborn deliveries between 85.9% and 92.9%. Avoidable outborn deliveries were mainly associated with gestational age, intrauterine growth restriction, preterm premature rupture of membranes, and haemorrhage, but not distance. CONCLUSIONS: Our study identified some modifiable risk factors for outborn delivery; however, when regionalised care relies heavily on antenatal transfer, as it does in France, only some outborn deliveries may be prevented. Earlier referral of high-risk women will be needed to achieve full access to tertiary care.

Infant outcome after active management of early-onset fetal growth restriction with absent or reversed umbilical artery blood flow.

OBJECTIVE: To describe the short- and long-term outcomes of infants with early-onset fetal growth restriction (FGR) and umbilical artery absent or reversed end-diastolic flow (AREDF), delivered before 30 weeks' gestation and managed proactively. METHODS: This was a retrospective cohort study of fetuses delivered for fetal indication before 30 completed weeks' gestation that had early-onset FGR (defined as estimated fetal weight more than 2 SD below the mean) with AREDF in the umbilical artery (FGR group), at the level-3 perinatal unit in Lund, Sweden, between 1998 and 2015. Perinatal outcome and neurodevelopment at ≥ 2 years of age in surviving infants were compared with those of a group of infants without small-for-gestational-age birth weight or any known fetal Doppler changes delivered before 30 weeks in Lund during the corresponding time period (non-FGR group). In the FGR group, the main indication for delivery was the Doppler finding of AREDF in the umbilical artery. RESULTS: There were 139 fetuses (of which 26% were a twin/triplet) in the FGR group and 946 fetuses (of which 28% were a twin/triplet) in the non-FGR group. The FGR infants had a median birth weight of 630 g (range, 340-1165 g) and gestational age at birth of 187 days (range, 164-209 days), as compared with 950 g (range, 470-2194 g) and 185 days (range, 154-209 days), respectively, in the non-FGR group. The rate of fetal mortality did not differ between the two groups (5.0% and 5.4% in the FGR and non-FGR groups, respectively). All seven intrauterine deaths in the FGR group occurred before 26 weeks' gestation. In the FGR group compared with the non-FGR group, severe intraventricular hemorrhage was less frequent and bronchopulmonary dysplasia and septicemia were more frequent (P = 0.008, P < 0.001 and P = 0.017, respectively). In the FGR group, the survival rate at 2 years (83% of liveborn infants) and the rate of cerebral palsy (7%) did not differ significantly from those in the non-FGR group (82% and 8%, respectively). The rate of survival without neurodevelopmental impairment was higher in the non-FGR group (83%) than in the FGR group (62%) (P < 0.001), as well as in infants in the FGR group delivered at or after 26 weeks (72%) compared with those delivered before 26 weeks (40%) (P = 0.003). Within the FGR group, outcomes were similar between twins and singletons and, in those who survived beyond 2 years, outcomes were similar between fetuses with absent and those with reversed end-diastolic flow in the umbilical artery. CONCLUSIONS: Infants delivered very preterm after severe FGR with AREDF in the umbilical artery had a similar rate of survival as did non-FGR infants of corresponding gestational age; however, they were at higher risk of neurodevelopmental impairment, the risk being most pronounced following birth before 26 weeks. Gestational age remains an important factor associated with the prognosis of early-onset FGR; nevertheless, the present results support the hypothesis, which should be tested prospectively, that fetuses with early-onset FGR and umbilical artery AREDF may benefit from early intervention rather than expectant management, and that umbilical artery Doppler findings could be incorporated into clinical protocols for cases very early in gestation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.