Dynamic interaction between fetal adversity and a genetic score reflecting dopamine function on developmental outcomes at 36 months

Cognitive and academic outcomes of large-for-gestational-age babies born at early term: A systematic review and meta-analysis

INTRODUCTION

Early induction of labor (37+0-38+6 gestational weeks) in large-for-gestational-age infants may reduce perinatal risks such as shoulder dystocia, but it may also increase the long-term risks of reduced cognitive abilities. This systematic review aimed to evaluate the cognitive and academic outcomes of large-for-gestational-age children born early term vs full term (combined or independent exposures).

MATERIAL AND METHODS

The protocol was registered in the PROSPERO database under the registration no. CRD42024528626. Five databases were searched from their inception until March 27, 2024, without language restrictions. Studies reporting childhood cognitive or academic outcomes after early term or large-for-gestational-age births were included. Two reviewers independently screened the selected studies. One reviewer extracted the data, and the other double-checked the data. The risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale. In addition to narrative synthesis, meta-analyses were conducted where possible.

RESULTS

Of the 2505 identified articles, no study investigated early-term delivery in large-for-gestational-age babies. Seventy-six studies involving 11 460 016 children investigated the effects of either early-term delivery or large-for-gestational-age. Children born at 37 weeks of gestation (standard mean difference, -0.13; 95% confidence interval, -0.21 to -0.05), but not at 38 weeks (standard mean difference, -0.04; 95% confidence interval, -0.08 to 0.002), had lower cognitive scores than those born at 40 weeks. Large-for-gestational-age children had slightly higher cognitive scores than appropriate-for-gestational-age children (standard mean difference, 0.06; 95% confidence interval, 0.01-0.11). Similar results were obtained using the outcomes of either cognitive impairment or academic performance.

CONCLUSIONS

No study has investigated the combined effect of early-term delivery on cognitive scores in large-for-gestational-age babies. Early-term delivery may have a very small detrimental effect on cognitive scores, whereas being large for gestational age may have a very small benefit. However, evidence from randomized controlled trials or observational studies is required.

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.

Multi-behavioral obesogenic phenotypes among school-aged boys and girls along the birth weight continuum

Evidence shows that extremes of birth weight (BW) carry a common increased risk for the development of adiposity and related cardiovascular diseases, but little is known about the role of obesogenic behaviors in this process. Moreover, no one has empirically examined whether the relationship between BW, obesogenic behaviors and BMI along the full low-to-high birthweight continuum reflects the U-shape pattern expected from common risk at both BW extremes. Our objective was to characterize physical activity, screen time, and eating behavior and their relationship to BMI as a function of BW among school-aged boys and girls. In this cross-sectional study, 460 children aged 6 to 12 years (50% boys) from Montreal, Canada provided information on sleeping time, screen time, physical activity levels, eating behavior (emotional, external and restrained eating) and anthropometrics (height, weight, BW) through parent reported questionnaires. BMI was normalized using WHO Standards (zBMI), and BW expressed as ratio using Canadian population standards (BW for gestational age and sex). Analyses were conducted using generalized linear models with linear and quadratic terms for BW, stratified by sex and adjusted for age, ethnicity and household income. In boys, physical activity and screen time showed U-shaped associations with BW, while physical activity had an inverted U-shaped in girls. Emotional and restrained eating had positive linear relations with BW in boys and girls. Sleep time and external eating were not associated with BW. A U-shaped relationship between BW and zBMI was found in boys but no association was found in girls. Only sleep (in boys and girls), and emotional eating (girls only) were related to zBMI and mediation of the BW-zBMI relationship was only supported for emotional eating. In conclusion, BW relates to obesogenic behaviors and BMI in both non-linear and linear ways, and these associations differed by sex.