Cognitive development of term small for gestational age children at five years of age

Small-for-Gestational-Age and Vocabulary and Achievement Test Scores at Age 9 Among Children Born at Term in a Contemporary U.S. Sample

INTRODUCTION

Children that are small-for-gestational-age (SGA) at birth are at an increased risk for cognitive impairment, even if born at term (37-41 weeks). This study examined associations between sex-specific SGA and vocabulary and achievement tests in 9 year old children born at term using a contemporary population-based US sample.

METHODS

A secondary data analysis was conducted on a sample of 2144 children born at term in 1998-2000 who participated in a US birth cohort study that oversampled non-marital births, which in the U.S. are associated with socioeconomic disadvantage and racial minority status. Vocabulary and achievement tests were administered to participants at age 9. Unadjusted and adjusted Ordinary Least Squares and logistic regression models of associations between SGA and test scores were estimated.

RESULTS

Sex-specific SGA was associated with 2-5 point lower test scores and 1-2 times the odds of scores less than 85 (> 1 SD below the national mean) across most outcomes. In adjusted models, measures of SGA were associated with low scores on the Woodcock-Johnson Applied Problems test (OR 2.257; 95% CI 1.434, 3.551) and the Woodcock-Johnson Passage Comprehension test (OR 1.554; 95% CI 1.132, 2.134).

CONCLUSION

The findings validate previous studies of SGA at term and cognitive outcomes and provide further evidence using a contemporary high-risk population-based US sample. The findings suggest that SGA children born at term should be recruited for early interventions to promote improved cognitive functioning in school.

Prenatal Predictors of Neurobehavioral Outcome in Children with Fetal Growth Restriction at 6 Years of Age: A Retrospective Cohort Study

(1) Background: Fetal growth restriction (FGR) increases the risk of adverse neurodevelopmental outcomes, especially in preterm newborns. This study aims to describe the behavioral results of FGR at 6 years of age and to demonstrate the relationship of certain predictive factors with this development. (2) Methods: This retrospective cohort study included 70 children born in 2015 at the University Hospital Carlos Haya, Málaga, Spain who had been exposed to FGR during pregnancy; neonatal and infant data were recorded retrospectively. Children were assessed prospectively at 6 years of age by means of a strengths and difficulties questionnaire (SDQ) to study behavioral outcomes. (3) Results: We demonstrated that there are higher behavioral disability rates in children exposed to FGR during pregnancy and, in particular, high rates of hyperactivity or conduct problems. We also proved a negative relationship between the birth weight percentile and the total behavioral scale score, along with a positive correlation between hyperactivity and the emotional and behavioral scales. Learning difficulties were more frequent in early-onset FGR than in late-onset FGR. (4) Conclusions: Our study of behavioral development has demonstrated higher behavioral disability rates in children with FGR at 6 years of age; specifically, high rates of hyperactivity or conduct problems. At the same time, we have proved a negative relationship between the birth weight percentile and the total behavioral scale score.

Maternal infections during pregnancy and child cognitive outcomes

Background

Maternal prenatal infections have been linked to children’s neurodevelopment and cognitive outcomes. It remains unclear, however, whether infections occurring during specific vulnerable gestational periods can affect children’s cognitive outcomes. The study aimed to examine maternal infections in each trimester of pregnancy and associations with children’s developmental and intelligence quotients. The ALSPAC birth cohort was used to investigate associations between maternal infections in pregnancy and child cognitive outcomes.

Methods

Infection data from mothers and cognition data from children were included with the final study sample size comprising 7,410 mother-child participants. Regression analysis was used to examine links between maternal infections occurring at each trimester of pregnancy and children’s cognition at 18 months, 4 years, and 8 years.

Results

Infections in the third trimester were significantly associated with decreased verbal IQ at age 4 (p < .05, adjusted R2 = 0.004); decreased verbal IQ (p < .01, adjusted R2 = 0.001), performance IQ (p < .01, adjusted R2 = 0.0008), and total IQ at age 8 (p < .01, adjusted R2 = 0.001).

Conclusion

Results suggest that maternal infections in the third trimester could have a latent effect on cognitive development, only emerging when cognitive load increases over time, though magnitude of effect appears to be small. Performance IQ may be more vulnerable to trimester-specific exposure to maternal infection as compared to verbal IQ. Future research could include examining potential mediating mechanisms on childhood cognition, such as possible moderating effects of early childhood environmental factors, and if effects persist in future cognitive outcomes.

The relationship between child development and small for gestational age among preschool children

Objectives

This study aimed to assess the impact of small for gestational age (SGA) on the development of Taiwanese preschool children using the Chinese Child Developmental Inventory (CCDI).

Materials and Methods

A total of 982 children were enrolled in this study between June 2011 and December 2015. The samples were divided into two groups: SGA (n = 116, mean age = 2.98) and non-SGA (n = 866, mean age = 3.33) groups. The development scores were based on the CCDI, which consist of eight dimensions of development between the two groups. The linear regression analysis was adopted to examine the relationship of SGA with child development.

Results

On average, the children in the SGA group scored less in all eight subitems of the CCDI than those in the non-SGA group. However, regression analysis revealed that there was no significant difference in both performance and delay frequency in the CCDI between the two groups.

Conclusion

SGA children had similar developmental scores in CCDI as non-SGA children for preschool age in Taiwan.

Neurodevelopment Outcome in Children with Fetal Growth Restriction at Six Years of Age: A Retrospective Cohort Study

OBJECTIVE

This study aimed to describe neurodevelopment in fetal growth restriction children at the age of six. Secondly, we tried to demonstrate influencing factors that can improve or exacerbate this development, as well as predictive factors that might select a population at risk to assist with early childhood support.

METHOD

It was a study of 70 children affected with FGR. FGR was based on these definitions: birth weight below the 3rd percentile or birth weight below the 10th percentile with an abnormal hemodynamic Doppler study. Neurodevelopment was assessed at 6 years old by means of Batelle Development Inventory. A global development quotient under a 100 score was considered a neurodevelopment delay. All variables regarding pregnancy care, delivery episode, postpartum, neonatal care, sociodemographic issues, and the need for support in the first years were studied.

RESULTS

The mean gestational age at diagnosis was 33.14 weeks (standard deviation (SD = 4.31), with 32.9% of early-onset diagnoses. The mean gestational age at delivery was 35.61 (SD = 3.21), and the cesarean rate was 64.3%. The average age of the children at the moment of the evaluation was 76.20-month-old (SD = 3.70). The mean global development quotient was 97.28 (SD = 13.97). We were able to record a 57.1% of global development delay. In the cases of cognition, only 17.1% of the children registered a delay. Motor and communication skills were the most frequently affected. We discovered that socioeconomic status was positively related to the global development quotient, as well as both gestational age at delivery and middle cerebral artery pulsatility index was positively related to the global development quotient.

CONCLUSIONS

We found a higher neurodevelopment delay rate (57.1%). We could relate a higher gestational age at delivery and a higher MCA percentile with better global neurodevelopment quotients.

Brain Sparing Effect on Neurodevelopment in Children with Intrauterine Growth Restriction: A Systematic Review

Background: Fetal growth restriction (FGR) is a pregnancy complication. Multiple studies have connected FGR to poor cognitive development, behavior disorders, and academic difficulties during childhood. Brain sparing has traditionally been defined as an adaptive phenomenon in which the brain obtains the blood flow that it needs. However, this adaptive phenomenon might not have a complete protective effect. This publication aims to systematically review the consequences of brain redistribution on neurodevelopment in children who presented with placental intrauterine growth restriction. Methods: We performed a systematic review according to PRISMA guidelines. It included studies on intrauterine growth restriction or small-for-gestational-age (SGA) fetuses, which middle cerebral artery was measured, and neurodevelopment assessed during childhood. PUBMED and EMBASE databases were searched for relevant published studies. Results: Of the 526 studies reviewed, only 12 were included. Brain sparing was associated with poor cognitive function and lower scores in IQ. Cerebral redistribution was related to better executive function and better behavior at 4 years old but not at 12 years old. Conclusions: We can assume that fetal brain sparing could not be a fully protective phenomenon. We could not find clinical differences in behavioral and executive functions because the results were heterogeneous. Some cognitive abilities could be affected in FGR brain sparing fetuses.

Term Birth Weight and Neurodevelopmental Outcomes

BACKGROUND

Preterm birth is an important risk factor for neurodevelopmental disabilities. The vast majority of these disabilities occur, however, among term births. The role of fetal growth restriction specifically among term babies has been incompletely described.

METHODS

We conducted a population-based study of term birth weight and its link to a range of neurodevelopmental outcomes using Norwegian health registries. To remove the influence of preterm birth, we restricted our analyses to 1.8 million singleton babies born during a narrow range of term gestational age (39-41 weeks). Babies with malformations were excluded. We adjusted analyses simply for year of birth, as further adjustments for sex, parity, maternal age, smoking, marital status, immigrant status, and parental education had trivial influence. An additional sibling analysis controlled for unmeasured family-based confounding.

RESULTS

The risk of neurodevelopmental disabilities at term steadily increased at birth weights lower than 3.5 kg. Using the category of 3.5-3.9 kg as the reference, the odds reached 25-fold for cerebral palsy at the smallest weights (95% confidence interval 8.0, 79), 16-fold for vision/hearing disability (4.0, 65), 11-fold for intellectual impairment (6.9, 17), 7-fold for schizophrenia (1.0, 50), 5.4-fold for epilepsy (2.6, 12), and 3.5-fold for autism spectrum (1.3, 9.4) and behavioral disorders including attention-deficit hyperactivity disorder (2.1, 5.4). Associations remained robust with sibling controls.

CONCLUSIONS

Reduced fetal growth is a powerful predictor of a wide variety of neurodevelopmental disabilities independent of preterm delivery.

The epidemiology of cognitive development

The epidemiology of cognitive development is an approach essentially based on large observational studies, which examines individual differences in cognitive abilities throughout childhood and their determinants. Although different in terms of methodology and main interests from developmental psychology, cognitive epidemiology offers complementary viewpoints on cognitive development and addresses fundamental research questions of interest to developmental psychologists. The present paper depicts the contributions of the epidemiological approach to the field of cognitive development and highlights the methodological advances that have made such contributions possible. We discuss the stability and developmental trajectories of cognitive functions, their main predictors, the complex interplay between environmental and genetic predictors, and the relationships between the different domains of cognition from birth to adulthood.

Antenatal corticosteroid administration and early school age child development: A regression discontinuity study in British Columbia, Canada

BACKGROUND

There are growing concerns that antenatal corticosteroid administration may harm children's neurodevelopment. We investigated the safety of antenatal corticosteroid administration practices for children's overall developmental health (skills and behaviors) at early school age.

METHODS AND FINDINGS

We linked population health and education databases from British Columbia (BC), Canada to identify a cohort of births admitted to hospital between 31 weeks, 0 days gestation (31+0 weeks), and 36+6 weeks, 2000 to 2013, with routine early school age child development testing. We used a regression discontinuity design to compare outcomes of infants admitted just before and just after the clinical threshold for corticosteroid administration of 34+0 weeks. We estimated the median difference in the overall Early Development Instrument (EDI) score and EDI subdomain scores, as well as risk differences (RDs) for special needs designation and developmental vulnerability (<10th percentile on 2 or more subdomains). The cohort included 5,562 births admitted between 31+0 and 36+6 weeks, with a median EDI score of 40/50. We found no evidence that antenatal corticosteroid administration practices were linked with altered child development at early school age: median EDI score difference of -0.5 [95% CI: -2.2 to 1.7] (p = 0.65), RD per 100 births for special needs designation -0.5 [-4.2 to 3.1] (p = 0.96) and for developmental vulnerability of 3.9 [95% CI:-2.2 to 10.0] (p = 0.24). A limitation of our study is that the regression discontinuity design estimates the effect of antenatal corticosteroid administration at the gestational age of the discontinuity, 34 + 0 weeks, so our results may become less generalisable as gestational age moves further away from this point.

CONCLUSIONS

Our study did not find that that antenatal corticosteroid administration practices were associated with child development at early school age. Our findings may be useful for supporting clinical counseling about antenatal corticosteroids administration at late preterm gestation, when the balance of harms and benefits is less clear.

Association of Intrauterine Growth Restriction and Small for Gestational Age Status With Childhood Cognitive Outcomes: A Systematic Review and Meta-analysis

IMPORTANCE

The magnitude of the association of intrauterine growth restriction (IUGR) and small for gestational age (SGA) status with cognitive outcomes in preterm and term-born children has not been established.

OBJECTIVE

To examine cognitive outcomes of preterm and term-born children who had IUGR and were SGA compared with children who were appropriate for gestational age (AGA) during the first 12 years of life.

DATA SOURCES

For this systematic review and meta-analysis, the Scopus, PubMed, Web of Science, Science Direct, PsycInfo, and ERIC databases were searched for English-language, peer-reviewed literature published between January 1, 2000, and February 20, 2020. The following Medical Subject Heading terms for IUGR and SGA and cognitive outcomes were used: intrauterine growth restriction, intrauterine growth retardation, small for gestational age AND neurodevelopment, neurodevelopmental outcome, developmental outcomes, and cognitive development.

STUDY SELECTION

Inclusion criteria were assessment of cognitive outcomes (full-scale IQ or a cognitive subscale), inclusion of an AGA group as comparison group, and inclusion of gestational age at birth and completion of cognitive assessment up to 12 years of age.

DATA EXTRACTION AND SYNTHESIS

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guidelines were followed. Data were double screened for full-text articles, and a subset were independently coded by 2 authors. Standardized mean differences (SMDs) and odd ratios from individual studies were pooled by applying random-effects models.

MAIN OUTCOMES AND MEASURES

Cognitive outcomes, defined as mental, cognitive, or IQ scores, estimated with standardized practitioner-based cognitive tests or as borderline intellectual impairment (BII), defined as mental, cognitive, or IQ scores at least 1 SD below the mean cognitive score.

RESULTS

In this study of 89 samples from 60 studies including 52 822 children, children who had IUGR and were SGA had significantly poorer cognitive outcomes (eg, cognitive scores and BII) than children with AGA in childhood. For cognitive scores, associations are consistent for preterm (SMD, -0.27; 95% CI, -0.38 to -0.17) and term-born children (SMD, -0.39; 95% CI, -0.50 to -0.28), with higher effect sizes reported for term-born IUGR and AGA group comparisons (SMD, -0.58; 95% CI, -0.82 to -0.35). Analyses on BII revealed a significantly increased risk in the preterm children who had IUGR and were SGA (odds ratio, 1.57; 95% CI, 1.40-1.77) compared with the children with AGA.

CONCLUSIONS AND RELEVANCE

Growth vulnerabilities assessed antenatally (IUGR) and at the time of birth (SGA) are significantly associated with lower childhood cognitive outcomes in preterm and term-born children compared with children with AGA. These findings highlight the need to develop interventions that boost cognitive functions in these high-risk groups.

Long-term care, from neonatal period to adulthood, of children born small for gestational age

Children born small for gestational age (SGA) face an increased risk of health problems in later life, particularly persistent short stature, neurocognitive dysfunction, impaired renal and pulmonary function, decreased bone density, sensorineural hearing loss, premature adrenarche, and metabolic syndrome. Insulin resistance appears to be a key component underlying these metabolic complications. Long-term, continuous, GH treatments in short children born SGA lead to a normalization of height through childhood to adulthood. Recombinant human GH has been proven to be relatively safe. We recommend early surveillance in a growth clinic for children born SGA without catch-up growth. Obesity, insulin resistance, and the risk of metabolic syndrome increase with catch-up growth, but short stature and cognitive dysfunction increase without catch-up growth in children born SGA. A solution to this catch-up dilemma is breast feeding for a minimum of 6 to 12 mo. Because the overall prevalence of metabolic risk factors is very low, routine evaluation of metabolic parameters is not recommended for all children born SGA, but it may be useful to consider metabolic evaluations in overweight or obese children born SGA. Since children born SGA have many risk factors, long-term management from neonate to adulthood is very important.

Stability of cognitive development during the first five years of life in relation to heavy metal concentrations in umbilical cord blood: Mothers' and Children's Environmental Health (MOCEH) birth cohort study

The objective of this study was to investigate stability of cognitive development during the first five years of life in relation to heavy metal concentrations in umbilical cord blood in Korean children. This research is part of the Mothers' and Children's Environmental Health (MOCEH) study, a multi-center prospective birth cohort study of pregnant women in Korea who were recruited from 2006 to 2010. We analyzed the complete follow-up data of children who were 5years-old in 2016. We measured lead, mercury, and cadmium levels in the umbilical cord blood of 251 children, and analyzed them, for whom neurodevelopmental data were available. We determined stability of cognitive development scores using three methods. First, we used partial correlation analyses to examine the stability of cognitive development at each measurement time. Second, we used Cramer's V to investigate the magnitude and direction of changes in cognitive development scores at each follow-up period among three groups (high, medium, and low scores). The results showed that cognitive development scores measured at the closest times had the strongest correlations, and the stability of cognitive development scores increased with age, from 6 to 60months. Groups at the extreme ends of cognitive development (high or low scores) had more stable scores, and this tendency was also stronger in infants >24months-old. The stability of cognitive development was unrelated to the umbilical cord level of heavy metals, based on analysis with Fisher's transformation. In conclusion, the present study showed that the cognitive development scores in a cohort of infants (6 to 60months-old) were stable.

Behavioral and intelligence outcome in 8- to 16-year-old born small for gestational age

Purpose

We investigated behavioral problems, attention problems, and cognitive function in children and adolescents born small for gestational age (SGA).

Methods

Forty-six SGA children born at term and 46 appropriate for gestational age (AGA) children born at term were compared. Psychiatric symptoms were examined with reference to the Korean-Child Behavior Checklist, Korean-Youth Self Report, and Attention Deficit Hyperactivity Disorder Rating Scale (ADHD-RS). Cognitive function was estimated using the Wechsler Intelligence Scale. Sociodemographic data were recorded from interviews.

Results

SGA children had high scores on delinquent behavior, aggressive behavior, and the externalizing scale, and they also showed a propensity for anxiety and depression. The SGA group had a higher mean ADHD-RS score than the AGA group (10.52±8.10 vs.9.93±7.23), but the difference was not significant. The SGA group had a significantly lower verbal intelligence quotient (IQ) than the AGA group, but the mean scores of both groups were within normal limits.

Conclusion

This study indicates marked behavioral problems, such as delinquency, aggressiveness, and anxiety and depression, as well as low verbal IQ in the SGA group than in the AGA group. Even in cases in which these symptoms are not severe, early detection and proper treatment can help these children adapt to society.

Progesterone supplementation for HIV-positive pregnant women on protease inhibitor-based antiretroviral regimens (the ProSPAR study): a study protocol for a pilot randomized controlled trial

Background

In Canada, the majority of HIV-positive pregnant women receive combination antiretroviral therapy that includes a ritonavir-boosted protease inhibitor to prevent mother-to-child HIV transmission. However, protease inhibitor-based combination antiretroviral therapy has been associated with increased rates of preterm, low birth weight, and small for gestational age births. Our previous experimental findings demonstrate that protease inhibitor use during pregnancy is associated with decreased progesterone levels that correlate with fetal growth, and that progesterone supplementation can improve protease inhibitor-induced fetal growth restriction. We hypothesize that HIV-positive pregnant women who receive protease inhibitor-based combination therapy may also benefit from progesterone supplementation during pregnancy.

Methods/design

In order to test this hypothesis, we have designed an open-label, multi-centre, randomized controlled (parallel group) pilot trial. The initial goal of this trial is to test feasibility and acceptability of our intervention. Forty HIV-positive pregnant women who are either on, or intending to start or switch to a boosted protease inhibitor-based combination antiretroviral regimen will be enrolled from six sites across Ontario, Canada. Twenty-five women will be randomized to self-administer natural progesterone (Prometrium, 200 mg) vaginally every night starting between gestational week 16 and 24 until week 36, and 15 women will be randomized to no intervention. While the participants and treating physicians will not be blinded, the laboratory personnel performing the biochemical and morphological evaluations will be blinded to ensure unbiased evaluation. The primary outcome of the pilot study is the feasibility of enrolment as measured by the recruitment rate and patient-reported reasons to decline participation. Secondary outcomes in participants include safety, acceptability, and adherence to progesterone supplementation.

Discussion

Given the safety of intravaginal progesterone and its current use in the general obstetrical population to prevent recurrent preterm delivery, this pilot study will provide data to determine the feasibility of a larger randomized controlled trial to assess the impact of this intervention on improving neonatal health in the context of HIV-positive pregnancies.

Trial registration

ClinicalTrials.gov, NCT02400021

Cognitive and Behavioral Outcomes of Intrauterine Growth Restriction School-Age Children

CONTEXT

Children who experienced intrauterine growth restriction (IUGR) may be at increased risk for adverse neurologic developmental outcomes during the school-age years of life.

OBJECTIVE

To estimate the effect of IUGR on cognition and behavior in school-aged children.

DATA SOURCES

Medline, Embase, and PsycINFO were searched for English-language articles published after 1980.

DATA SELECTION

We included case-control studies reporting cognitive and/or behavioral data of children who had IUGR and were evaluated afterfifth birthday.

DATA EXTRACTION

Cognitive data from 15 studies and behavioral data from 6 studies were selected with a total of 1559 cases and 1630 controls. The cognitive scores and behavioral outcomes were extracted.

RESULTS

The controls had significantly higher cognitive scores than the children with IUGR (standardized mean difference [SMD] -0.38, 95% confidence interval [CI] -0.51 to -0.25, P < .00001). The IQ scores of the IUGR group were not significantly correlated with mean birth weight and gestational age (P > .05). Five trials were included in the behavioral outcomes trial, the behavior scores were significantly different between the groups with and without IUGR (SMD 0.31, 95% CI 0.13 to 0.48, P = .001). The incidence of attention-deficit/hyperactivity disorder (ADHD) was not significantly different between 2 groups (P = .11).

LIMITATIONS

The number of studies that assessed behavioral and ADHD outcome is small.

CONCLUSIONS

The findings demonstrate that IUGR is associated with lower cognitive scores in school-age children. However, further large-scale trials are needed to assess the effects of IUGR on the outcome of behavioral disorder and ADHD.

Early growth patterns are associated with intelligence quotient scores in children born small-for-gestational age

OBJECTIVE

To assess whether patterns of growth trajectory during infancy are associated with intelligence quotient (IQ) scores at 4 years of age in children born small-for-gestational age (SGA).

METHODS

Children in the Collaborative Perinatal Project born SGA were eligible for analysis. The primary outcome was the Stanford-Binet IQ score at 4 years of age. Growth patterns were defined based on changes in weight-for-age z-scores from birth to 4 months and 4 to 12 months of age and consisted of steady, early catch-up, late catch-up, constant catch-up, early catch-down, late catch-down, constant catch-down, early catch-up & late catch-down, and early catch-down & late catch-up. Multivariate linear regression was used to assess associations between patterns of growth and IQ.

RESULTS

We evaluated patterns of growth and IQ in 5640 children. Compared with children with steady growth, IQ scores were 2.9 [standard deviation (SD)=0.54], 1.5 (SD=0.63), and 2.2 (SD=0.9) higher in children with early catch-up, early catch-up and later catch-down, and constant catch-up growth patterns, respectively, and 4.4 (SD=1.4) and 3.9 (SD=1.5) lower in children with early catch-down & late catch-up, and early catch-down growth patterns, respectively.

CONCLUSIONS

Patterns in weight gain before 4 months of age were associated with differences in IQ scores at 4 years of age, with children with early catch-up having slightly higher IQ scores than children with steady growth and children with early catch-down having slightly lower IQ scores. These findings have implications for early infant nutrition in children born SGA.

Preterm small-for-gestational age children: predictive role of gestational age for mental development at the age of 2 years

AIM

The aim of the study was to compare the cognitive development of very low birth weight (VLBW) preterm SGA children and preterm AGA children at the age of 2 years. The hypothesis was that SGA children are at an additional risk for deficits in cognitive function. Additionally, the impact of neonatal risk factors and the parents' profession on the early cognitive development was analysed.

METHODS

Cognitive function of 107 preterm infants with a gestational age of 24-35 weeks was assessed with the Mental Bayley Scales of Infant Development at the age of 2 years (mean±SEM). The results of SGA (n=38) and AGA (n=69) children were compared as well as neonatal risk factors and parental education.

RESULTS

There was a linear regression between the Mental Bayley Scales result and gestational age for preterm infants with a gestational age of 24-32 weeks. SGA and AGA children did not differ significantly in their cognitive function at the age of 2 years. A strong association was found between the parents' profession and cognitive development. Among the neonatal risk factors, bronchopulmonary dysplasia was a strong predictor of mental development.

INTERPRETATION

Cognitive development of two-year-old preterm children with a gestational age of 24-32 weeks was mainly related to their gestational age. Being born preterm and small for gestational age was not additionally associated with cognitive deficits at the age of 2 years. The parents' profession had a significant impact on the cognitive development. The role of the parents' profession on the early development of preterm infants should be elucidated in further studies.

Functional outcomes at age 7 years of moderate preterm and full term children born small for gestational age

OBJECTIVE

To compare functional outcomes of 7-year-old (school-age) children born small for gestational age (SGA; ie, a birth weight z score ≤ -1 SD), with appropriate for gestational age (AGA) peers, born moderately preterm or full term.

STUDY DESIGN

Data were collected as part of the Longitudinal Preterm Outcome Project study, a community-based, prospective cohort study of 336 AGA and 42 SGA born children (median gestational age 35 weeks, range 31-41). Of the SGA children, 32 were moderately preterm, 10 were full term; of the AGA, these numbers were 216 and 120, respectively. At 6.9 years, we assessed intelligence, verbal memory, attention, visuomotor integration, and motor skills and we collected the parent-reported executive functioning. We compared the outcomes of the SGA children with those of their AGA peers.

RESULTS

The performance of SGA children was similar to that of their AGA peers, except for attention control which was abnormal more often in SGA children (OR 3.99, 95% CI 1.32-12.12). The IQ of SGA children was 3 points lower, but this difference failed to reach significance.

CONCLUSIONS

At school age, children born SGA have a greater risk of abnormal test scores on attention control than children born AGA, independent of gestational age. Their motor and many other cognitive functions are similar. The impact of these outcomes seems limited. Nevertheless, the consequences for school performance deserve attention.

Birth weight and cognitive function in early adulthood: the Australian Aboriginal birth cohort study

It has been suggested that in addition to genetic factors, fetal and post-natal growth influence cognition in early adulthood. However, most studies have been in developed populations, so it is unclear if the same findings would be seen in other, less developed, settings, and have used testing tools not applicable to an Australia Aboriginal population. This study investigated the relationships between cognitive function in early adulthood and birth weight and contemporary height. Simple reaction time (SRT), choice reaction time (CRT) and working memory (WM) were assessed using the CogState battery. A significant association was seen between birth weight and SRT in early adulthood, but not with the other two cognitive measures. Urban dwellers had significantly shorter SRT and CRT than their remote counterparts. Contemporary body mass index and maternal age were associated with CRT. Only fetal growth restriction was associated with WM, with greater WM in those with restricted growth. No associations were seen with contemporary height. These results suggest that fetal growth may be more important than the factors influencing post-natal growth in terms of cognition in early adulthood in this population, but that the associations may be inconsistent between cognitive outcomes. Further research is required to identify whether similar associations are seen in other, similar, populations and to assess why differences in cognitive outcome measures are seen.

Growth restriction alters adult spatial memory and sensorimotor gating in a sex-specific manner

In Western society, impaired uteroplacental blood flow is the major cause of human intrauterine growth restriction. Infants born small and who experience late childhood accelerated growth have an increased risk of developing adult diseases. Recent studies also suggest a link between birth weight and altered adult behavior, particularly relating to motor function, learning and memory, depression and schizophrenia. The aim of this study was to determine the relative influence of prenatal and postnatal growth restriction on adult behavioral outcomes in male and female rats. Uteroplacental insufficiency was induced in Wistar Kyoto rats by bilateral uterine vessel ligation on day 18 of gestation producing growth-restricted offspring (Restricted group). The Control group had sham surgery. Another group underwent sham surgery, with a reduction in litter size to five at birth equivalent to the Restricted litter size (Reduced Litter group). At 6 months of age, a series of behavioral tests were conducted in male and female offspring. Growth restriction did not impair motor function. In fact, Restricted and Reduced Litter males showed enhanced motor performance compared with Controls (P < 0.05). Spatial memory was greater in Restricted females only (P < 0.05). The Porsolts test was unremarkable, however, males exhibited more depressive-like behavior than females (P < 0.05). A reduction in sensorimotor gating function was identified in Reduced Litter males and females (P < 0.05). We have demonstrated that growth restriction and/or a poor lactational environment can affect adult rat behavior, particularly balance and coordination, memory and learning, and sensorimotor gating function, in a sex-specific manner.

Cohort profile: The Cork BASELINE Birth Cohort Study: Babies after SCOPE: Evaluating the Longitudinal Impact on Neurological and Nutritional Endpoints

The Cork BASELINE Birth Cohort Study (Babies After

SCOPE

Evaluating the Longitudinal Impact on Neurological and Nutritional Endpoints) was established with three main objectives: to investigate the effects of intrauterine growth restriction and early nutrition on metabolic health and neurodevelopment; to ascertain the incidence and determinants of food allergy and eczema in early childhood; and to describe early infant feeding, supplementation and nutritional status and their effects on physical and neurological growth and health outcomes. The SCOPE Ireland pregnancy cohort formed the basis of recruitment of infants to BASELINE [n 1537] and an additional 600 infants were recruited after delivery providing a total sample of 2137 between 2008 and 2011. Assessments were at day 2 and at 2, 6, 12 and 24 months, with 5-year assessments ongoing. Blood and DNA samples were biobanked at 15 and 20 weeks' gestation, birth, 24 months and 5 years. Body composition data were collected at 2 days and 2 months (air-displacement plethysmography) and at 5 years (dual-energy X-ray absorptiometry). Trans-epidermal water loss was measured at 2 days, 2, 6 and 24 months. Detailed dietary and validated developmental assessments were conducted at 24 months. Researchers interested in collaboration can contact [baseline@ucc.ie] and further information be found at [http://www.baselinestudy.net/ or http://www.birthcohorts.net/].

Socioeconomic status, child enrichment factors, and cognitive performance among preschool-age children: results from the Follow-Up of Growth and Development Experiences study

Lower cognitive performance is associated with poorer health and functioning throughout the lifespan and disproportionately affects children from lower socioeconomic status (SES) populations. Previous studies reporting positive associations between child home enrichment and cognitive performance generally had a limited distribution of SES. We evaluated the associations of SES and child enrichment with cognitive performance in a population with a wide range of SES, particularly whether enrichment attenuates associations with SES. Children were sampled from a case-control study of small-for-gestational-age (SGA) conducted in a public hospital serving a low SES population (final n=198) and a private hospital serving a middle-to-high SES population (final n=253). SES (maternal education and income) and perinatal factors (SGA, maternal smoking and drinking) were obtained from maternal birth interview. Five child home enrichment factors (e.g. books in home) and preschool attendance were obtained from follow-up interview at age 4.5 years. Cognitive performance was assessed with the Differential Ability Scales (DAS), a standardized psychometric test administered at follow-up. SES and enrichment scores were created by combining individual factors. Analyses were adjusted for perinatal factors. Children from the public birth hospital had a significantly lower mean DAS general cognitive ability (GCA) score than children born at the private birth hospital (adjusted mean difference -21.4, 95% CI: -24.0, -18.7); this was substantially attenuated by adjustment for individual SES, child enrichment factors, and preschool attendance (adjusted mean difference -5.1, 95% CI: -9.5, -0.7). Individual-level SES score was associated with DAS score, beyond the general SES effect associated with hospital of birth. Adjustment for preschool attendance and home enrichment score attenuated the association between individual SES score and adjusted mean DAS-GCA among children born at both of the hospitals. The effect of being in the lower compared to the middle tertile of SES score was reduced by approximately a quarter; the effect of being in the upper compared to the middle tertile of SES score was reduced by nearly half, but this comparison was possible only for children born at the private hospital. A child's individual SES was associated with cognitive performance within advantaged and disadvantaged populations. Child enrichment was associated with better cognitive performance and attenuated the SES influence. Health care providers should reinforce guidelines for home enrichment and refer children with delays to early intervention and education, particularly children from disadvantaged populations.

Ischemic placental disease and risks of perinatal mortality and morbidity and neurodevelopmental outcomes

Preeclampsia, intrauterine growth restriction, and placental abruption are serious obstetrical complications that constitute the syndrome of ischemic placental disease and account for a disproportionate degree of perinatal morbidity and mortality. We review the risks of stillbirth and neonatal and infant mortality in relation to ischemic placental disease, focusing on population-based studies. We also review the risks of neonatal morbidity and neurodevelopmental outcomes in relation to ischemic placental disease. A synthesis of the findings of the relevant studies relating ischemic placental disease to adverse perinatal outcomes underscores two important observations. First, despite the low prevalence of each of the three obstetrical complications, all are associated with increased risks of adverse perinatal and infant outcomes, as well as neurodevelopmental deficits. Second, the burden of increased perinatal risks appears strongest during the preterm period. Efforts to reduce the risks of ischemic placental disease remain critically important and developing effective clinical interventions will be a target worthy for consideration.

A neonatal piglet model for investigating brain and cognitive development in small for gestational age human infants

The piglet was investigated as a potential model for studying brain and cognitive deficits associated with being born small for gestational age (SGA). Naturally farrowed SGA (0.7-1.0 kg BW) and average for gestational age (AGA, 1.3-1.6 kg BW) piglets were obtained on postnatal day (PD) 2, placed in individual cages, and provided a nutritionally adequate milk replacer diet (285 ml/kg/d). Beginning at PD14, performance in a spatial T-maze task was assessed. At PD28, piglets were anesthetized for magnetic resonance (MR) imaging to assess brain structure (voxel-based morphometry), connectivity (diffusion-tensor imaging) and metabolites in the hippocampus and corpus callosum (proton MR spectroscopy). Piglets born SGA showed compensatory growth such that BW of SGA and AGA piglets was similar (P>0.05), by PD15. Birth weight affected maze performance, with SGA piglets taking longer to reach criterion than AGA piglets (p<0.01). Total brain volume of SGA and AGA piglets was similar (P<0.05), but overall, SGA piglets had less gray matter than AGA piglets (p<0.01) and tended to have a smaller internal capsule (p = 0.07). Group comparisons between SGA and AGA piglets defined 9 areas (≥ 20 clusters) where SGA piglets had less white matter (p<0.01); 2 areas where SGA piglets had more white matter (p<0.01); and 3 areas where SGA piglets had more gray matter (p<0.01). The impact of being born SGA on white matter was supported by a lower (p<0.04) fractional anisotropy value for SGA piglets, suggesting reduced white matter development and connectivity. None of the metabolites measured were different between groups. Collectively, the results show that SGA piglets have spatial learning deficits and abnormal development of white matter. As learning deficits and abnormalities in white matter are common in SGA human infants, the piglet is a tractable translational model that can be used to investigate SGA-associated cognitive deficits and potential interventions.

Neuropsychological deficits in young adults born small-for-gestational age (SGA) at term

Reduced IQ, learning difficulties and poor school performance have been reported in small-for-gestational-age (SGA) subjects. However, few studies include a comprehensive neuropsychological assessment. Our aim was to study neuropsychological functioning in young adults born SGA at term. A comprehensive neuropsychological test battery was administered to 58 SGA subjects (birth weight <10th centile) born at term, and 81 term non-SGA controls (birth weight ≥10th centile). The SGA group obtained significantly (p < .01) lower scores on the attention, executive and memory domains compared to non-SGA controls and showed higher risk of obtaining scores below -1.5 SD on the memory domain (odds ratio = 13.3, 95% confidence interval: 1.57, 112.47). At a subtest level, the SGA group obtained lower scores on most neuropsychological tests, with significant differences on 6 of 46 measures: the Trail Making Test 3 (letter sequencing), the Wechsler Memory Scale mental control and the auditory immediate memory scale, the Design Fluency, the Stroop 3 (inhibition) and the Visual Motor Integration (VMI) motor coordination subtest. Young adults born SGA score more poorly on neuropsychological tests compared with non-SGA controls. Differences were modest, with more significant differences in the memory domain.

Pathways of neuronal and cognitive development in children born small-for-gestational age or late preterm

OBJECTIVE

To assess the effects of late small-for-gestational-age (SGA) birth and late prematurity on cognitive outcomes and structural changes in the central nervous system at primary school age, using a novel approach to examine changes in neuronal integrity of the retina.

METHODS

We conducted a cross-sectional study of 347 children aged 6-13 years, including in the analysis only infants born after 34 weeks' gestation. We recorded all perinatal outcomes through a survey of parents. Neuronal damage was evaluated using optical coherence tomography of the retina. In a subgroup of 112 children aged 6-8 years, visuospatial perception was evaluated with the Children's Bender Visual Motor Gestalt Test.

RESULTS

The proportions of SGA and late preterm children were 11.8 and 6.3%, respectively. Prematurity and SGA were simultaneously present in five children. When compared with controls, SGA children showed significantly lower than average retinal nerve fiber layer (RNFL) thickness (94.1 vs 98.8 μm; P = 0.007) and an increased percentage of abnormal Bender scores (27.3 vs 6.2%; P = 0.017) (odds ratio 5.6 (95% CI, 1.2-26.8)). These differences increased when late SGA infants with a birth weight below the 3(rd) percentile were compared with SGA infants with a birth weight between the 3(rd) and 10(th) percentiles and with controls, for RNFL thickness (92.5 vs 94.6 and 98.8 μm, respectively; P = 0.021) and abnormal Bender tests (33.3 vs 25.0 and 6.2%, respectively; P = 0.036). However, no differences were found in retinal structure and visuomotor performance between late preterm and term infants.

CONCLUSIONS

These data suggest that late SGA and late prematurity induce a distinct neuronal pattern of structural changes that persist at school age. Late-onset SGA infants are at increased risk for axonal loss in the retina and present specific visuomotor difficulties.

Small for gestational age and intrauterine growth restriction decreases cognitive function in young adults

OBJECTIVE

To examine the effect on adult cognitive function of being born small for gestational age (SGA), and to evaluate whether cognitive function is related to intrauterine growth restriction (IUGR).

STUDY DESIGN

Fifty-nine SGA subjects (birth weight <10th percentile) and 81 controls (birth weight ≥10th percentile) born at term underwent cognitive assessment with the Wechsler Adult Intelligence Scale-Third Edition at age 19-20 years. Repeated ultrasound measures of fetal growth were available for weeks 25, 33, and 37 in a subgroup of 29 SGA subjects and 75 control subjects, and these were data used to dichotomize the 29 SGA subjects into those with IUGR and those without IUGR. IUGR was defined as growth deviating more than -2 SD from the mean value of the control group. The effect of maternal smoking during pregnancy was considered as well. Group differences were analyzed using a general linear model, controlling for sex and socioeconomic status.

RESULTS

The SGA group had lower full IQ scores than the control group (mean difference, -6.3; 95% CI, -2.8 to -9.7; P = .001), including lower scores on 6 of the Wechsler Adult Intelligence Scale-Third Edition subtests. In the SGA subgroup with repeated ultrasound measures, 6 of 29 subjects (21%) had IUGR, and these subjects also had a lower IQ compared with controls (mean difference, -14.0; 95% CI: -4.8 to -23.3; P = .003). Maternal smoking during pregnancy was related to lower IQ in the control group but not in the SGA group, independent of IUGR or non-IUGR status.

CONCLUSION

IQ scores were lower in young adults born SGA compared with controls. Our analysis suggest that this outcome is related to IUGR.

Neurodevelopmental delay in small babies at term: a systematic review

OBJECTIVE

Being small for gestational age (SGA) or having fetal growth restriction (FGR) may be associated with poorer neurodevelopmental outcomes compared to being appropriate for gestational age (AGA). The aim of this paper was to evaluate the existence and magnitude of decrease in neurodevelopmental scores in SGA and FGR infants born at term from a systematic review of the existing literature.

METHODS

Studies of neurodevelopment in SGA/FGR babies were identified from a search of the internet scientific databases. Studies that included preterm births and those that did not define absolute indices of standardized cognitive outcome were excluded. SGA was defined as birth weight below the 10(th) centile for gestation and FGR as the same birth-weight standard with abnormal umbilical artery Doppler ultrasound or evidence of abnormal placentation on pathology specimen studies. Effect size was calculated as the standardized mean difference between neurodevelopment scores of controls and SGA/FGR children.

RESULTS

There were 28 studies of SGA, with a total of 7861 SGA and 91 619 control AGA babies, and three studies of FGR, with a total of 119 FGR and 49 control AGA babies. Data synthesis showed that standardized neurodevelopmental scores in SGA babies were 0.32 SD (95% CI, 0.25-0.38) below those for normal controls, though with heterogeneity between studies (I(2) = 68.3%). Insufficient data were available for FGR babies.

CONCLUSION

The findings of the study demonstrate that among babies born at term, being SGA is associated with lower scores on neurodevelopmental outcomes compared to AGA controls. A trial designed to evaluate the effects of intervention in small fetuses born at term in order to improve the neurodevelopmental outcome is urgently needed.

Axonal loss and cognitive deficits in term infants with normal umbilical artery Doppler born small-for-gestational age

OBJECTIVE

To assess cognitive outcomes and structural changes in the central nervous system, the latter using a novel approach to examine changes in neuronal integrity of the optic nerve, in children at 5-6½ years of age who were born small-for-gestational age (SGA) at term having shown normal umbilical artery (UA) Doppler.

METHODS

We compared neuronal damage, cognitive deficits and visuospatial perception in two cohorts of infants, one born SGA (n = 40) and one born appropriate-for-gestational age (AGA) (n = 39) in weight. Neuronal damage was evaluated using optical coherence tomography (OCT) of the optic nerve. Cognitive deficits were assessed with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) test. Visuospatial perception was evaluated with Rey-Osterreich Complex Figure (ROCF) tasks.

RESULTS

Children from the SGA group had a significantly thinner average retinal nerve fiber layer (RNFL) compared with those from the AGA group (98.2 vs 104.5 µm, P = 0.012). Children from the SGA group exhibited impaired performance in copy tasks on the ROCF (3.27 vs 3.56, P = 0.036) and a higher rate of suboptimal WPPSI test performance intelligence quotient scores (15% vs 0%; P = 0.025) compared with those from the AGA group.

CONCLUSION

Term infants with normal UA Doppler born SGA are at increased risk for cognitive deficits and axonal loss in the RNFL at the age of 5-6½ years.

Early childhood development when second-trimester ultrasound dating disagrees with last menstrual period: a prospective cohort study

BACKGROUND

When an ultrasound-based estimate of gestational age (GA) is less (greater) than an estimate based on a definite last menstrual period, the fetus may grow slower (faster) than average. While the association between these discrepancies in GA estimates and adverse perinatal outcomes has been examined extensively, there is scant evidence about long-term effects, such as child neurodevelopment.

METHODS

Using data from a prospective cohort study titled, NICHD Study of Successive Small-for-Gestational Age Births, we examined if GA discrepancies in early second trimester of pregnancy (17 weeks' gestation) are associated with: (1) impaired motor and mental function at 13 months (measured using Bayley Scales of Infant Development (Bayley)), and (2) impaired cognitive development at five years (assessed by Wechsler Preschool and Primary Scale of Intelligence - Revised Intelligence Quotient (WPPSI-R)) in the infant. The study population consisted of 572 (30% of the overall sample of 1,945) women who presented for prenatal care in Norway and Sweden between 1986 and 1988.

RESULTS

Our results showed that GA discrepancies in early second trimester are significantly associated with birthweight. We found no significant relationship, however, with the Bayley development scores at 13 months and with the WPPSI-R IQ measures at five years.

CONCLUSIONS

GA discrepancies at 17 weeks' gestation are not associated child neurodevelopment. These discrepancies do, however, relate to birthweights, providing a basis for detecting fetal growth patterns early in the second trimester of pregnancy. Our study, however, was unable to evaluate the impact of first-trimester discrepancies on impaired neurodevelopment in the infant.

Intrauterine growth and neuropsychological performance in very low birth weight preschoolers

In this study we examined the association between intrauterine growth, indexed either as a categorical variable or continuous dimension, and neuropsychological outcome, in a very low birth weight (VLBW) sample of 143 preschoolers. When the commonly used split at the 10th percentile rank was applied to classify intrauterine growth restriction (IUGR), we found that the growth restricted group (n = 25) exhibited significantly poorer performance in the global motor domain, but not on any other neuropsychological measure. In contrast, when adequacy of intrauterine growth was indexed by standardized birth weight, a continuous dimension, this early risk factor explained a unique portion of the variance in global cognitive abilities and visuospatial skills, as well as in global, fine, and gross motor skills. These findings are consistent with recent magnetic resonance imaging data disclosing global neurodevelopmental changes in the brains of preterm infants with IUGR. When cases classified with IUGR (<10th percentile) were excluded, the relationship between adequacy of intrauterine growth and global cognitive abilities remained significant despite range restriction. Hence, an association between appropriateness of intrauterine growth and global intellectual outcome may be observed even within the population of VLBW preschoolers with adequate standardized birth weight.

Neonatal outcomes after influenza immunization during pregnancy: a randomized controlled trial

BACKGROUND

There are limited data about the effect of maternal influenza infection on fetuses and newborns. We performed a secondary analysis of data from the Mother's Gift project, a randomized study designed to test the effectiveness of inactivated influenza and pneumococcal vaccines during pregnancy.

METHODS

In the Mother's Gift project, 340 pregnant women in Bangladesh received either inactivated influenza vaccine or 23-valent pneumococcal polysaccharide vaccine (control). This study was performed from August 2004 through December 2005. We performed a secondary analysis of outcomes following maternal influenza immunization during two periods: when influenza virus was not circulating (September 2004 through January 2005) and when influenza virus was circulating (February through October 2005). We assessed gestational age, mean birth weight and the proportion of infants who were small for gestational age.

RESULTS

During the period with no circulating influenza virus, there were no differences in the incidence of respiratory illness with fever per 100 person-months among mothers and infants in the two groups (influenza vaccine: 3.9; control: 4.0; p > 0.9). The proportion of infants who were small for gestational age and the mean birth weight were similar between groups (small for gestational age: influenza vaccine 29.1%, control 34.3%; mean birth weight: influenza vaccine 3083 g, control 3053 g). During the period with circulating influenza virus, there was a substantial reduction in the incidence per 100 person-months of respiratory illness with fever among the mothers and infants who had received the influenza vaccine (influenza vaccine: 3.7; control: 7.2; p = 0.0003). During this period, the proportion of infants who were small for gestational age was lower in the influenza vaccine group than in the control group (25.9% v. 44.8%; p = 0.03). The mean birth weight was higher among infants whose mothers received the influenza vaccine than among those who received the control vaccine during this period (3178 g v. 2978 g; p = 0.02).

INTERPRETATION

During the period with circulating influenza virus, maternal immunization during pregnancy was associated with a lower proportion of infants who were small for gestational age and an increase in mean birth weight. These data need confirmation but suggest that prevention of influenza infection in pregnancy can influence intrauterine growth.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT 00142389.

Global and regional differences in brain anatomy of young children born small for gestational age

In children who are born small for gestational age (SGA), an adverse intrauterine environment has led to underdevelopment of both the body and the brain. The delay in body growth is (partially) restored during the first two years in a majority of these children. In addition to a negative influence on these physical parameters, decreased levels of intelligence and cognitive impairments have been described in children born SGA. In this study, we used magnetic resonance imaging to examine brain anatomy in 4- to 7-year-old SGA children with and without complete bodily catch-up growth and compared them to healthy children born appropriate for gestational age. Our findings demonstrate that these children strongly differ on brain organisation when compared with healthy controls relating to both global and regional anatomical differences. Children born SGA displayed reduced cerebral and cerebellar grey and white matter volumes, smaller volumes of subcortical structures and reduced cortical surface area. Regional differences in prefrontal cortical thickness suggest a different development of the cerebral cortex. SGA children with bodily catch-up growth constitute an intermediate between those children without catch-up growth and healthy controls. Therefore, bodily catch-up growth in children born SGA does not implicate full catch-up growth of the brain.

Does the individualized reference outperform a simple ultrasound-based reference applied to birth weight in predicting child neurodevelopment?

OBJECTIVES

Being small-for-gestational age (SGA) is associated with an increased risk of morbidity, but questions remain about how best to diagnose SGA, and thus, predict poor health consequences. The authors sought to compare an individualized reference for defining SGA with simple birth weight-based and ultrasound-based references applied to birth weight in predicting poor cognitive development at age five.

METHODS

The authors used data from the Successive SGA Births Study, a prospective study including 699 Alabaman and 618 Scandinavian women recruited from 1986 to 1988, and whose children had cognitive development scores measured at age five using the Wechsler Preschool and Primary Scale of Intelligence-Revised Intelligence Quotient. Sensitivity, specificity and positive predictive value (PPV) were estimated for each reference applied to birth weight using adverse cognitive development (score < 10(th) percentile) as the outcome. Relative risk of poor neurodevelopment was calculated, comparing infants classified as SGA by either the individualized or the simple ultrasound-based reference with infants not classified as SGA.

RESULTS

The individualized reference had higher specificity and PPV in predicting poor neurodevelopment. Neonates defined as SGA by the individualized reference alone had a higher risk (RR=2.20, 95% CI: 1.20, 4.00) of poor cognitive outcome, while those identified by the ultrasound-based reference alone did not (RR=0.95, 95% CI: 0.45, 2.01). None of the references could predict poor neurodevelopment well at age five.

CONCLUSIONS

The individualized birth weight reference modestly outperforms the simple ultrasound-based reference in identifying SGA infants with poor child neurodevelopment. However, neither reference can predict child neurodevelopment well.

Recém-nascido pequeno para a idade gestacional: repercussão nas habilidades motoras finas

OBJETIVO: Comparar as habilidades motoras finas de lactentes nascidos a termo pequenos para a idade gestacional (PIG) com as habilidades dos nascidos adequados para a idade gestacional (AIG) no terceiro mês de vida. MÉTODOS: Realizou-se um estudo observacional de corte transversal. Avaliaram-se 67 lactentes (21 PIG e 46 AIG) no terceiro mês de vida. Portadores de síndromes genéticas, malformações congênitas, infecções congênitas e aqueles que necessitaram de unidade de terapia intensiva neonatal foram excluídos. As Escalas Bayley II de Desenvolvimento Infantil foram utilizadas, com ênfase nos itens que avaliam as habilidades motoras finas. RESULTADOS: Não se observaram diferenças entre os grupos na escala motora (p=0,21) e mental (p=0,45) no terceiro mês de vida. No item "Alcança o Aro Suspenso", houve diferença significativa (teste Exato de Fisher; p=0,02), demonstrando maior frequência de execução para o grupo PIG no terceiro mês de vida. CONCLUSÕES: Supõe-se que a diferença encontrada no item "Alcança o Aro Suspenso" possa ser atribuída à grande ocorrência de movimentos dos braços observada no grupo PIG e não a uma condição melhor de desenvolvimento desse grupo.

Socioeconomic differences and the impact of being small for gestational age on neurodevelopment among preschool-aged children

BACKGROUND

Studies of small for gestational age (SGA) birth and subsequent childhood cognitive outcomes are inconsistent. Few studies have assessed whether effects varied by socioeconomic status (SES).

OBJECTIVE

To assess child cognitive and behavioral outcomes according to SGA and severe SGA (<10th and <5th percentiles) and SES.

METHODS

We followed 474 infants initially selected for a case-control study assessing SGA vs. appropriate-for-gestational age (AGA). The infants were born at two hospitals: a public hospital serving a low-income, African-American population and a private hospital serving a predominantly white, middle-class population. At age 54 months, a psychologist administered the Differential Abilities Scales (DAS), and Vineland Adaptive Behavior Scales (VABS). The mother completed the Child Behavior Checklist (CBCL). Associations were analyzed using multiple linear regression.

RESULTS

Among AGA children, the mean DAS score was >1 standard deviation lower for children born at the public vs. the private hospital (75.2 vs. 95.7 among boys; 76.3 vs. 101.8 among girls). Being SGA had a weaker effect on DAS scores, overall. Severe SGA had a significant effect on DAS scores of children born at the private hospital (average reduction 8.0 +/- 2.5 points), but not on children born at the public hospital (average reduction 1.1 +/- 2.2 points). In the latter group, severe SGA was associated with a lower VABS score (average reduction 9.2 +/- 2.5 points).

CONCLUSIONS

Poor fetal growth influences neurodevelopment, but this influence is modified by postnatal environment. Adverse effects associated with low SES might mask or attenuate associations between prenatal exposures and developmental outcomes in some populations.

Cerebral MRI and cognition in nonhandicapped, low birth weight adults

This study sought to compare cognitive and cerebral findings of magnetic resonance imaging in young adults with low birth weights and in a control group. One hundred thirteen of 173 (65%) eligible adults with birth weights <2000 g, and 100 of 170 (59%) controls, all without major disabilities, were examined at age 19 years. Cerebral 3.0 T magnetic resonance imaging was performed according to standardized protocols. Prorated intelligence quotient was estimated from two subtests of the Wechsler Abbreviated Scale of Ability, a word comprehension test, and matrices. Prominent lateral ventricles and loss of white matter, and thinning of the corpus callosum, were more common in the low birth weight group than in the control group (40% vs. 15%, respectively; odds ratio, 3.8; P < 0.001; and 31% vs. 7%, respectively; odds ratio, 6.0; P < 0.001). Low birth weight adults exhibited lower mean intelligence quotients (95 vs. 101, respectively; P < 0.001). Low birth weight adults face an increased risk of prominent ventricles, global loss of white matter, and thinning of the corpus callosum. Similar magnetic resonance imaging findings are not uncommon among healthy adults.

Timing and trajectories of fetal growth related to cognitive development in childhood

The authors investigated timing and trajectories of fetal growth in relation to childhood development in the National Institute of Child Health and Human Development-Scandinavian Study of Successive Small-for-Gestational Age Births (1986-1988) (n = 1,059). Fetal size was assessed by ultrasound at 17, 25, and 33 gestational weeks and at birth. Bayley Scales of Infant Development and the Wechsler Preschool and Primary Scale of Intelligence-Revised tests were conducted at ages 1 and 5 years, respectively, producing mental and psychomotor development indexes and verbal and performance intelligence quotients. Relative fetal size was calculated as a standard deviation score at each data point; growth trajectories were explored with longitudinal mixture models. Fetal size at 17, 25, and 33 weeks was positively associated with mental development index; larger size at 33 weeks and at birth was associated with higher verbal intelligence quotient scores (2.61, 95% confidence interval: 1.06, 4.15 and 1.90, 95% confidence interval: 0.67, 3.13 increase per 1 standard deviation score, respectively); findings were similar for performance intelligence quotient. Seven trajectories were identified; scores were lower for "small" and "medium-to-small" trajectories than for "medium" and "big" (representing normal size) trajectories: mental development index (P < 0.01), performance intelligence quotient (P < 0.001), and verbal intelligence quotient (P < 0.001). Overall, larger fetal size in the second and third trimesters was positively associated with childhood development. Fetal growth trajectories may matter beyond birth.

Age of sitting unsupported and independent walking in very low birth weight preterm infants with normal motor development at 2 years

AIMS

The aims of this study is to (i) determine the age of sitting unsupported and independent walking in preterm infants with birth weight under 1500 g (very low birth weight, VLBW); (ii) estimate differences between VLBW children and a reference population and (iii) estimate the association between clinical characteristics and late age at sitting and walking.

METHODS

A longitudinal study was conducted of a cohort of 876 children with VLBW. The World Health Organization (WHO) motor development study population was used as a reference. Ages for both skills were established by interview with parents. Means were compared with t-test, ANOVA and Bonferroni adjustment where appropriate.

RESULTS

The inclusion criteria were complied with 694 patients; 50% of VLBW sat at 7 m corrected age (CA) and walked at 13 m CA. Both motor skills were acquired later (7.3 +/- 1.5 and 13.6 +/- 2.8 m) compared with the control group (6 +/- 1.1 and 12.1 +/- 1.8 m). Weight or head circumference at birth below the 10th percentile or the presence of bronchopulmonary dysplasia were associated with delayed acquisition of both skills.

CONCLUSION

Very low birth weight infants typically sit unsupported and walk later than term infants. Tables describing reference values for milestones acquisition for different categories of infants (gestational age, birth weight and other determinants) may contribute to inform the decision making process on access to available resources.

Determinants of cognitive ability at 7 years: a longitudinal case-control study of children born small-for-gestational age at term

The aim of this study was to identify the determinants of children's intelligence at 7 years, including pregnancy, postnatal, demographic factors, and small-for-gestational age (SGA) birth at term. Information was collected at birth (n = 871), 1 year (n = 744), 3.5 years (n = 550), and 7 years (n = 591). Approximately half of the children in this study were born SGA (birthweight <or=10th percentile). There was no significant difference found between IQ scores for SGA children compared to AGA children, after adjustment for potential confounders (p = 0.45). Paternal education, developmental delay, and birth order were associated with intelligence scores at 7 years in the multiple regression analysis. This study found no long-term effect of SGA birth at term on intelligence in middle childhood. Potentially modifiable postnatal and demographic factors were found to be strong predictors of intelligence at 7 years.

Lifespan influences on mid- to late-life cognitive function in a Chinese birth cohort

OBJECTIVE

To explore factors throughout the lifespan that influence cognition in midlife to late life.

METHODS

We conducted a retrospective birth cohort study of 2,062 individuals born during 1921-1954 in Beijing, China. In 2003-2005, birth records were abstracted, and participants then 50-82 years old received standardized examinations for health, cognition, and socio-environmental measures. Using cumulative logit models, we assessed adjusted relative effects of prenatal, early life, and adult factors on mid- to late-life cognition.

RESULTS

Most prenatal factors were associated with mid- to late-life cognition in the unadjusted models. However, when childhood and adult factors were sequentially added to the models, the impact of prenatal factors showed successive attenuation in effect size, and became insignificant. In contrast, early life factors remained significantly associated with mid- to late-life cognition even after full life-course adjustments. Specifically, those whose fathers had laborer vs professional occupations (odds ratio [OR](Laborer) 1.74; 95% confidence interval [CI]: 1.25-2.42) had poorer cognitive outcomes, while individuals who drank milk daily in childhood (OR 0.65; 95% CI: 0.54-0.80), had more years of education (OR(10-12 years) 0.60; 95% CI: 0.45-0.81; OR(13+ yrs) 0.29; 95% CI: 0.23-0.38), and were taller adults (OR(height > or = SD) 0.65; 95% CI: 0.49-0.86) had better cognition. The high prenatal risk infants had similar patterns with a trend toward a stronger association between cognition and socioenvironmental factors.

CONCLUSION

Mid- to late-life cognition is influenced by factors over the entire lifespan with the greatest impact coming from early life exposures. Nutrition, education, social, and family environment in early life may have a long-term impact on cognition in developing countries.

Growth patterns in children with intrauterine growth retardation and their correlation to neurocognitive development

The relationship between somatic growth and neurocognitive outcome was studied in a cohort of 136 children with intrauterine growth retardation. The children were followed up from birth to 9 to 10 years of age by annual measurements of growth parameters, neurodevelopmental evaluations, and IQ. The rate of catch-up for height between 1 and 2 years of age was significantly higher than the catch-up for weight (P < .001). The cognitive outcome at 9 to 10 years correlated with head circumference at all ages. The neurodevelopmental outcome at 9 to 10 years correlated with weight at all ages. Correlation with head circumference was more significant with IQ, while with weight it was stronger with the neurodevelopmental score. Height at 1 year was a significant predictor for IQ and neurodevelopmental outcome at 9 to 10 years. These findings are of distinct importance for prediction of subsequent neurodevelopmental outcome in children with intrauterine growth retardation.

[Maternal occupation, pregnancy length and low birth weight]

OBJECTIVE

To assess the association between maternal occupation during pregnancy with the presence of low birth weight and preterm delivery.

METHOD

The sample consisted of 1,341,686 preterm infants and 1,217,897 low birth weight infants in Spain (1996-2000) with valid information on maternal occupation from the National Registry of Births. Maternal occupation was the main exposure variable coded according to groups of occupation (CNO-79) and outcomes were low birth weight (<2500 g) and preterm birth (<37 weeks). Crude and adjusted odds ratios (OR) and 95% confidence interval (CI) were calculated through the maximum verisimilitude method.

RESULTS

The highest prevalence of preterm infants was found in mothers working in agriculture (10.8%) and the lowest in professional women (6.6%). The highest prevalence of low birth weight was observed in the women working in the services sector (3.5%) and manual workers in industry and construction (3.4%) while the lowest prevalence was found in professional women (2.5%). Women working in agriculture had a higher risk of preterm birth than professional women (aOR=1.68; 95%CI: 1.57-1.80). The risk of low birth weight was higher in women working in the service sector (aOR=1.36; 95%CI: 1.30-1.42), housewives (aOR=1.30; 95%CI: 1.28-1.38), agricultural laborers (aOR=1.29; 95%CI: 1.14-1.44) and manual workers in industry and construction (aOR=1.29; 95%CI: 1.21-1.36).

CONCLUSIONS

The results of this study suggest that belonging to certain occupational groups during pregnancy could affect the risk of low birth weight and preterm birth.

Head circumference and long-term outcome in small-for-gestational age infants

OBJECTIVES

To assess risk factors for the growth and development of small-for-gestational age (SGA) infants whose birth weight was less than the 10(th) percentile.

PATIENTS AND METHODS

SGA infants who were admitted to the neonatal intensive care unit from 1995 to 1998 were enrolled in the study. Fifty-six SGA infants, having no chromosomal abnormalities, inherited diseases, TORCH infections, major anomaly and/or multiple birth, were divided into 34 asymmetrical and 22 symmetrical SGA infants by >or= or <10(th) percentile head circumference (HC) at birth. The physical growth including HC, and the developmental quotient (DQ) and intelligent quotient (IQ) scores were evaluated up to 6 years of age.

RESULTS

Symmetrical SGA infants had lower levels of weight, height and HC, but not of total DQ at 3 years or IQ scores at 6 years of age than asymmetrical SGA infants. The 21 SGA infants who had a HC less than the 10(th) percentile at 1 year of age (non-catch-up group) showed lower total DQ (mean 96 vs. 105) and IQ (82 vs. 102) scores than 34 SGA infants who had not (catch-up group).

CONCLUSIONS

These results suggested that psychomotor development of SGA infants depended on the HC at 1 year of age rather than that at birth.

Low birth weight, prematurity, and paternal social status: impact on the basic competence test in Taiwanese adolescents

OBJECTIVE

To investigate whether birth weight and paternal education may have independent and interactive effects on the learning achievement of adolescents.

STUDY DESIGN

We linked birth weights, gestational ages (term or preterm) and paternal education of a 4-year birth cohort to the Basic Competence Test (BCT) scores in Mandarin, mathematics and science for junior high school students age 15 to 16 years. The study groups comprised infants with term low birth weight (TLBW; n = 33 507), preterm normal birth weight (PNBW; n =19 905), and preterm low birth weight (PLBW; n = 25 840), as well as randomly selected term infants with normal birth weight (TNBW; n = 83 756). Paternal education levels were categorized.

RESULTS

Compared with the TNBW adolescents, the TLBW adolescents consistently showed larger deficits in mean scores for Mandarin (beta = -2.36), mathematics (beta = -2.89), and science (beta = -2.11). The corresponding significant deficit scores for the PLBW adolescents were -1.93, -2.80, and -1.92. The deficit scores were very small for the PNBW adolescents. Paternal education was inversely associated with scores of all 3 groups. Lower paternal education level tended to worsen the negative impact of low birth weight on BCT scores.

CONCLUSIONS

Both lower birth weight and lower paternal education exert an independent and interactive effect on adolescent learning achievement.

Effects of being born small for gestational age on long-term intellectual performance

Size at birth has been associated repeatedly with increased risk of cardiovascular morbidity and mortality later in life. However, there is accumulating evidence to suggest an association between being born small for gestational age (SGA) and increased risk of lower intelligence, poor academic performance, low social competence and behavioural problems, compared with individuals born appropriate for gestational age. Crude neurological handicaps, such as cerebral palsy, are extremely rare in children born SGA at term. Such handicaps are more common in very premature children. However, there does appear to be an increase in the risk for non-severe neurological dysfunction in individuals born SGA. Intellectual performance is evaluated in young children in several different ways, including standardized tests such as Weschler's Intelligence Scale - Revised, and teachers and parents' reports. In adulthood, indirect variables such as education and occupation are used in addition to standardized tests. It may be possible to modify the effects of SGA on intellectual development by breast feeding the baby for more than 6 months. Nutrient-enriched formula does not have any advantages when it comes to intellectual development, and induces a risk of rapid weight gain and eventually overweight. Growth hormone treatment may also have some effect on intelligence quotient.