Etiological Subgroups of Small-for-Gestational-Age: Differential Neurodevelopmental Outcomes

Maternal gestational weight gain and the long-term physical and neurological outcome of small for gestational age children: A 4-year real-world study based on a longitudinal cohort

BACKGROUND

Globally, small for gestational age (SGA) is increasingly prevalent, paralleling the common high-risk pregnancies with inappropriate gestational weight gain (GWG). However, whether maternal GWG was associated with their SGA offspring's long-term development remained unresolved.

OBJECTIVE

To examine the associations of maternal GWG with the long-term physical and neurological development of SGA children based on a real-world cohort in our hospital.

STUDY DESIGN

This retrospective cohort was conducted at our hospital between July 1, 2020, and December 2022. At baseline, we included 319 children diagnosed as SGA and followed up with these children for 12 to 48 months (median: 29 months). The primary outcomes were children's physical and neurological development at follow-ups which were grouped into those with inadequate, adequate, or excessive maternal GWG. We standardized the weight, height (length), body mass index, and ASQ-3 / ASQ:SE domain scores of children with different ages and genders into Z-scores to increase comparability. The adjusted odds ratio (OR) and its 95 % confidence interval (CI) controlling for covariates were calculated using the Hosmer-Lemeshow test model to assess the risk of impaired neurodevelopment.

RESULTS

Firstly, the birth weight and birth length of newborns in the inadequate GWG group were both smaller than those in the adequate GWG group and excessive GWG group. The proportions of severe SGA, neonatal respiratory distress syndrome, and bronchopulmonary dysplasia were higher in the inadequate GWG group compared to the adequate GWG group. Secondly, follow-up observations found that inadequate GWG group had significantly lower weight Z scores(0.12 vs 0.34), height Z scores(-0.11 vs 0.32)and high emaciation incidence (14.3 % vs. 5.0 %) compared to the adequate GWG group. Thirdly, in the follow-up of the neurodevelopment, children in the adequate GWG group had statistically higher Z scores in the gross motor, fine motor, problem-solving and personal-social domains compared to those in the inadequate GWG group and had statistically higher Z scores in the gross motor domain compared to those in the excessive GWG group; children in the excessive GWG group had statistically higher Z scores in the fine motor and personal-social domains compared to those in the inadequate GWG group. Inadequate GWG group was significantly correlated with a higher risk of delayed development in gross motor (OR 1.79, 95 % CI 1.15-2.77), fine motor (OR 1.6, 95 % CI 1.06-2.78), problem-solving (OR 2.08, 95 % CI 1.16-3.56), personal-social (OR 1.51, 95 % CI 1.05-2.18), and social-emotional (ASQ:SE) (OR 1.84, 95 % CI 1.05-3.22) domains than adequate GWG group. Meanwhile, excessive GWG group was significantly correlated with a higher risk of delayed development in gross motor (OR 1.6, 95 % CI 1.02-2.48) domain than adequate GWG group.

CONCLUSION

Inappropriate maternal GWG (inadequate or excessive) may affect the long-term physical and neurological development of SGA infants. Pregnant women, especially those with intrauterine growth restriction, need to maintain reasonable GWG and receive close monitoring and timely interventions to improve SGA children' long-term outcomes.

Feeding Method, Nicotine Exposure, and Growth during Infancy

Objective

To answer 3 questions: (1) Are infants breastfed by smokers at risk of rapid weight and length gain? (2) Is rapid growth during infancy partially attributable to ingestion of smokers' breastmilk? (3) If so, what are the implications for breastfeeding by smokers?

Study design

Using data from the Norwegian Mother, Father and Child Cohort Study and Medical Birth Registry of Norway (n = 54 522), we examined changes in weight, length, weight-for-length z-score (WFLZ) during infancy in the context of maternal smoking (0, 1-10, or >10 cigarettes/day) and feeding method during the first 6 months (breastfed, formula fed, mixed fed). We fit generalized linear models, adding a smoking by feeding method interaction term to evaluate the effect of ingesting smokers' breastmilk.

Results

Breastfed infants of both light and heavy smokers experienced WFLZ gains of 0.05 (95% CI, 0.01-0.09) and 0.13 (95% CI, 0.07-0.18), respectively. Among mixed-fed infants, only heavy maternal smoking predicted WFLZ gain (0.10; 95% CI, 0.05-0.16). Among exclusively formula-fed infants, maternal smoking did not predict rapid growth. Interaction models suggest that infants ever breastfed (ie, breastfed and mixed-fed groups combined) by heavy smokers gained weight (100 g; 95% CI, 30-231) and length (2.8 mm; 95% CI, 0.1-5.6), attributable to ingesting smoker's breastmilk.

Conclusions

Infants breastfed by smokers experience rapid growth; some of these gains are attributable to ingesting smokers' breastmilk. Among infants breasted by light smokers, these gains are within the range of normative growth patterns for healthy, breastfed infants.

The Legacy of the COVID-19 Pandemic: Impact on Infant and Maternal and Health from an Appalachian Academic Medical Center

BACKGROUND/OBJECTIVES

The COVID-19 pandemic period from 2020 to 2022 had a significant impact on maternal infant health with mothers impacted more than their infants. We questioned whether there have been any lingering effects from the pandemic.

METHODS

We examined intermediate and long-term pandemic effects on maternal and neonatal outcomes before, during, and after the COVID-19 pandemic period. We reviewed mother-infant pairs from the following three epochs: (1) the pre-COVID-19 period, (2) the COVID-19 pandemic period, and (3) the post-pandemic period. The Case Mix Index (CMI) for the neonates from all three epochs were detailed.

RESULTS

Post-pandemic, we noted a rising trend of LGA infants (10%) and an increase in SGA infants (13%). For women in 2023, we noted an increase in hypertension, preeclampsia, diabetes, and a higher BMI than in the pre-pandemic period. There have also been more congenital anomalies (9%), and neonatal CMI increased in the post-pandemic period.

CONCLUSIONS

Well after the pandemic period, maternal-infant health continues to be affected. For women, the increase in hypertension and diabetes during pregnancy is concerning. For infants, being LGA or SGA may have long-term consequences. The post-pandemic increase in infants with congenital anomalies compared to the pre-pandemic era is an area that needs ongoing review.

The Association between Infant Birth Weight, Head Circumference, and Neurodevelopmental Outcomes

OBJECTIVE

The aim of this study was to evaluate whether being small for gestational age (SGA) or large for gestational age (LGA) or having a small or large head circumference (HC) at birth is associated with adverse neurodevelopmental outcomes.

STUDY DESIGN

This is a secondary analysis of a multicenter negative randomized trial of thyroxine therapy for subclinical hypothyroid disorders in pregnancy. The primary outcome was child intelligence quotient (IQ) at 5 years of age. Secondary outcomes included several neurodevelopmental measures. Associations between the outcomes in children with SGA (<10th percentile) or LGA (>90th percentile) birth weights, using ethnicity- and sex-specific population nomogram as well as nomograms from the National Fetal Growth (NFG) study, were compared with the referent of those with appropriate for gestational age (AGA) birth weight. Similar analyses were performed for HC.

RESULTS

Using the population nomogram, 90 (8.2%) were SGA and 112 (10.2%) were LGA. SGA neonates were more likely to be born preterm to mothers who were younger, smoked, and were less likely to have less than a high school education, whereas LGA neonates were more likely to be born to mothers who were older and have higher body mass index, compared with AGA neonates. SGA at birth was associated with a decrease in the child IQ at 5 years of age by 3.34 (95% confidence interval [CI], 0.54-6.14) points, and an increase in odds of child with an IQ < 85 (adjusted odds ratio [aOR], 1.9; 95% CI, 1.1-3.2). There was no association between SGA and other secondary outcomes, or between LGA and the primary or secondary outcomes. Using the NFG standards, SGA at birth remained associated with a decrease in the child IQ at 5 years of age by 3.14 (95% CI, 0.22-6.05) points and higher odds of an IQ < 85 (aOR, 2.3; 95% CI, 1.3-4.1), but none of the other secondary outcomes. HC was not associated with the primary outcome, and there were no consistent associations of these standards with the secondary outcomes.

CONCLUSION

In this cohort of pregnant individuals with hypothyroid disorders, SGA birth weight was associated with a decrease in child IQ and greater odds of child IQ < 85 at 5 years of age. Using a fetal growth standard did not appear to improve the detection of newborns at risk of adverse neurodevelopment.

Prenatal tobacco smoke exposure and risk for cognitive delays in infants born very premature

Prenatal tobacco smoke exposure (TSE) and prematurity are independent risk factors for abnormal neurodevelopment. The objectives were to compare differences in Bayley-III cognitive, language, and motor scores at 2 years corrected age (CA) in 395 infants born very preterm (≤ 32 weeks gestation) with and without prenatal TSE. We performed multivariable linear regression analyses to examine associations between prenatal TSE and neurodevelopmental outcomes and a mediation analysis to estimate direct effects of prenatal TSE on outcomes and indirect effects through preterm birth. In total, 50 (12.6%) infants had prenatal TSE. Infants with prenatal TSE had lower mean [95% CI] Cognitive score (82.8 [78.6, 87.1]) vs. nonexposed infants (91.7 [90.1, 93.4]). In children with and without prenatal TSE, there were significant differences in mean [95% CI] Language scores (81.7 [76.0, 87.4] vs. 92.4 [90.2, 94.6], respectively) and mean [95% CI] Motor scores (86.5 [82.2, 90.7] vs. 93.4 [91.8, 95.0], respectively); scores remained significant after controlling for confounders. Preterm birth indirectly mediated 9.0% of the total effect of prenatal TSE on Cognitive score (P = NS). However, 91% of the remaining total effect was significant and attributable to TSE's direct harmful effects on cognitive development (β = - 5.17 [95% CI - 9.97, - 0.38]). The significant association is largely due to TSE's direct effect on cognitive development and not primarily due to TSE's indirect effect on preterm birth.

Prenatal environment and developmental trajectories: the intrauterine growth restriction

The prenatal environment is of fundamental importance for the fetus, as the fetus is particularly susceptible to environmental influences while in utero, and several prenatal adversities may constitute a risk factor for fetal growth and child development. Intrauterine growth restriction (IUGR) refers to a pregnancy complication involving the inadequate growth of the fetus in utero, with potential programming consequences on the children's brain-behavior development. In this narrative review we will discuss the most recent literature about IUGR children, including their development and their relationship with the prenatal and postnatal environment. In particular, as an attempt to an adaptive response to intrauterine changes, the brain development of IUGR fetuses follows abnormal developmental pathways, which likely has cascade effects on the future neurodevelopmental outcomes of the children. Cognitive and motor functions are in fact impaired, as well as IUGR children present, across studies, poor socio-emotional abilities and a greater risk for internalizing and externalizing behavior problems. The current work also highlights how the postnatal environment, and in particular parental care, has an important role in IUGR development, acting as a protective factor, or otherwise increasing their constitutional vulnerabilities. Overall, this narrative review has important implications for clinical practice, suggesting the need for long-term follow-up care with IUGR children and strategies supporting parent-child interactions as well.

Etiological subgroups of term small-for-gestational-age and childhood health outcomes

BACKGROUND

Small-for-gestational-age (SGA) has a heterogeneous etiology. Our study aimed to examine the childhood health outcomes of etiology-distinct term SGA subgroups.

METHODS

Data from the Collaborative Perinatal Project were used. The etiological factors of SGA were categorized into five groups: maternal, fetal, placental, environmental and physiological factors. Primary child outcomes included low IQ and growth restriction. A total of 8417 term infants were eligible.

RESULTS

Compared with AGA, SGA children due to fetal factors had the highest risk of low IQ (aOR = 1.94, 95% CI: 1.45-2.59). SGA infants due to physiological factors had the highest risk of growth restriction (aOR = 6.04, 95% CI: 3.93-9.27). SGA children had a higher risk of growth restriction with the aOR ranging from 3.05 (95% CI: 2.36-3.96) to 5.77 (95% CI: 4.29-7.75) for the number of risk factors that the SGA infants had from 1 to 5. SGA children with any risk factor were associated with a higher risk of lower IQ with the aOR ranging from 1.59 (95% CI: 1.31-1.94) to 1.96 (95% CI: 1.50-2.55). SGA without the five types of etiologies was not associated with adverse child outcomes except for growth restriction (aOR = 3.82, 95% CI: 2.62-5.55).

CONCLUSION

Term SGA of different etiologies may lead to different child health outcomes.

IMPACT

Our study found that SGA of different etiologies may lead to different child health outcomes. Compared with AGA, SGA children due to fetal factors had the highest risk of low IQ. SGA infants due to physiological factors had the highest risk of growth restriction. SGA babies should not be treated the same. In the era of precision medicine, our findings may help pediatricians and parents better manage SGA babies according to different etiologies and the number of risk factors.

The Impact of Selective Fetal Growth Restriction or Birth Weight Discordance on Long-Term Neurodevelopment in Monochorionic Twins: A Systematic Literature Review

The aim of this review was to assess the impact of selective fetal growth restriction (sFGR) and/or birth weight discordance (BWD) on long-term neurodevelopment in monochorionic (MC) twins. Five out of 28 articles assessed for eligibility were included. One article concluded that the incidence of long-term neurodevelopmental impairment (NDI) was higher in BWD MC twins (11/26, 42%) than in BWD dichorionic (DC) (5/38, 13%) and concordant MC twins (6/71, 8%). BWD MC twins had a 6-fold higher risk of cerebral palsy compared to DC twins (5/26, 19% vs. 1/40, 3%, p < 0.05). Another article described a linear relationship between birth weight and verbal IQ scores, demonstrating a 13-point difference for a 1000 gram BWD between the twins, with a disadvantage for the smaller twin (p < 0.0001). Three articles analyzing within-pair differences showed that the smaller twin more frequently demonstrated mild NDI (6/80, 8% vs. 1/111, 1%) and lower developmental test scores (up to 5.3 points) as opposed to its larger co-twin. Although these results suggest that MC twins with sFGR/BWD are at increased risk of long-term NDI as compared to BWD DC or concordant MC twins, with a within-pair disadvantage for the smaller twin, the overall level of evidence is of moderate quality. As only five articles with a high degree of heterogeneity were available, our review mainly demonstrates the current lack of knowledge of the long-term outcomes of MC twins with sFGR/BWD. Insight into long-term outcomes will lead to improved prognostics, which are essential in parent counseling and crucial in the process of forming a management protocol specifically for twins with sFGR to optimally monitor and support their development.