Disproportionate fetal growth and the risk for congenital cerebral palsy in singleton births

The associations between maternal and fetal exposure to endocrine-disrupting chemicals and asymmetric fetal growth restriction: a prospective cohort study

Recent evidence has revealed associations between endocrine-disrupting chemicals (EDCs) and placental insufficiency due to altered placental growth, syncytialization, and trophoblast invasion. However, no epidemiologic study has reported associations between exposure to EDCs and asymmetric fetal growth restriction (FGR) caused by placenta insufficiency. The aim of this study was to evaluate the association between EDC exposure and asymmetric FGR. This was a prospective cohort study including women admitted for delivery to the Maternal Fetal Center at Seoul St. Mary's Hospital between October 2021 and October 2022. Maternal urine and cord blood samples were collected, and the levels of bisphenol-A (BPA), monoethyl phthalates, and perfluorooctanoic acid in each specimen were analyzed. We investigated linear and non-linear associations between the levels of EDCs and fetal growth parameters, including the head circumference (HC)/abdominal circumference (AC) ratio as an asymmetric parameter. The levels of EDCs were compared between fetuses with and without asymmetric FGR. Of the EDCs, only the fetal levels of BPA showed a linear association with the HC/AC ratio after adjusting for confounding variables (β = 0.003, p < 0.05). When comparing the normal growth and asymmetric FGR groups, the asymmetric FGR group showed significantly higher maternal and fetal BPA levels compared to the normal growth group (maternal urine BPA, 3.99 μg/g creatinine vs. 1.71 μg/g creatinine [p < 0.05]; cord blood BPA, 1.96 μg/L vs. -0.86 μg/L [p < 0.05]). In conclusion, fetal exposure levels of BPA show linear associations with asymmetric fetal growth patterns. High maternal and fetal exposure to BPA might be associated with asymmetric FGR.

Influence of chest/head circumference ratio at birth on obstetric and neonatal outcomes: The Japan environment and children's study

OBJECTIVES

Some newborns that are not small-for-gestational-age (non-SGA, birthweight ≥10th percentile for a given gestational age) may have pathologic growth restrictions. This study examined the association of adverse obstetric and neonatal outcomes with chest/head circumference ratio at birth in non-SGA and SGA newborns.

METHODS

This study was a cross-sectional evaluation of data from a nationwide prospective birth cohort study, the Japan Environment and Children's Study. We analyzed 93 690 non-anomalous singletons born at 34-41 gestational weeks. We defined low, normal, and high chest/head circumference ratio as <10th percentile, 10th-90th percentile, and >90th percentile, respectively, according to the internally constructed chest/head circumference percentile chart. Modified Poisson regression was used to estimate adjusted prevalence ratios (aPR) for the outcomes studied.

RESULTS

Compared with non-SGA newborns with a normal ratio, those with a low ratio had an increased occurrence of low birthweight (1.75, 1.58-1.94 [aPR, 95% confidence interval]), cesarean delivery (1.34, 1.29-1.38), Apgar score <7 at 5 min (1.57, 1.14-2.17), respiratory complications (1.20, 1.04-1.39), and prolonged hospitalization (1.36, 1.30-1.42). In contrast, the high-ratio group had a lower rate of low birthweight (0.71, 0.59-0.86), cesarean delivery (0.82, 0.77-0.87), and prolonged hospitalization (0.83, 0.78-0.89). In SGA newborns, a low ratio was associated with increased aPRs for low birthweight, cesarean delivery, hypoglycemia, and prolonged hospitalization, whereas a high ratio showed no such association.

CONCLUSIONS

Findings indicate that the chest/head circumference ratio at birth influence obstetric and neonatal outcomes regardless of the birthweight status.

In utero Exposure to Maternal Diabetes and the Risk of Cerebral Palsy: A Population-based Cohort Study

BACKGROUND

Evidence on the effects of in utero exposure to maternal diabetes on cerebral palsy (CP) in offspring is limited. We aimed to examine the effects of pregestational (PGDM) and gestational diabetes (GDM) separately on CP risk and the mediating role of increased fetal size.

METHODS

In a population-based study, we included all live births in Ontario, Canada, between 2002 and 2017 followed up through 2018 (n = 2,110,177). Using administrative health data, we estimated crude and adjusted associations between PGDM or GDM and CP using Cox proportional hazards models to account for unequal follow-up in children. For the mediation analysis, we used marginal structural models to estimate the controlled direct effect of PGDM (and GDM) on the risk of CP not mediated by large-for-gestational age (LGA).

RESULTS

During the study period, 5,317 children were diagnosed with CP (187 exposed to PGDM and 171 exposed to GDM). Children of mothers with PGDM showed an increased risk (hazard ratio [HR]: 1.84 [95% confidence interval (CI): 1.59, 2.14]) after adjusting for maternal sociodemographic and clinical factors. We found no associations between GDM and CP (adjusted HR: 0.91 [0.77, 1.06]). Our mediation analysis estimated that LGA explained 14% of the PDGM-CP association.

CONCLUSIONS

In this population-based birth cohort study, maternal pregestational diabetes was associated with increased risk of CP, and the increased risk was not substantially mediated by the increased fetal size.

The Effect of Size and Asymmetry at Birth on Brain Injury and Neurodevelopmental Outcomes in Congenital Heart Disease

Poor and asymmetric fetal growth have been associated with neonatal brain injury (BI) and worse neurodevelopmental outcomes (NDO) in the growth-restricted population due to placental insufficiency. We tested the hypothesis that postnatal markers of fetal growth (birthweight (BW), head circumference (HC), and head to body symmetry) are associated with preoperative white matter injury (WMI) and NDO in infants with single ventricle physiology (SVP) and d-transposition of great arteries (TGA). 173 term newborns (106 TGA; 67 SVP) at two sites had pre-operative brain MRI to assess for WMI and measures of microstructural brain development. NDO was assessed at 30 months with the Bayley Scale of Infant Development-II (n = 69). We tested the association between growth parameters at birth with the primary outcome of WMI on the pre-operative brain MRI. Secondary outcomes included measures of NDO. Newborns with TGA were more likely to have growth asymmetry with smaller heads relative to weight while SVP newborns were symmetrically small. There was no association between BW, HC or asymmetry and WMI on preoperative brain MRI or with measures of microstructural brain development. Similarly, growth parameters at birth were not associated with NDO at 30 months. In a multivariable model only cardiac lesion and site were associated with NDO. Unlike other high-risk infant populations, postnatal markers of fetal growth including head to body asymmetry that is common in TGA is not associated with brain injury or NDO. Lesion type appears to play a more important role in NDO in CHD.

Intrauterine growth restriction followed by oxygen support uniquely interferes with genetic regulators of myelination

Intrauterine growth restriction (IUGR) and oxygen exposure in isolation and combination adversely affect the developing brain, putting infants at risk for neurodevelopmental disability including cerebral palsy. Rodent models of IUGR and postnatal hyperoxia have demonstrated oligodendroglial injury with subsequent white matter injury (WMI) and motor dysfunction. Here we investigate transcriptomic dysregulation in IUGR with and without hyperoxia exposure to account for the abnormal brain structure and function previously documented. We performed RNA sequencing and analysis using a mouse model of IUGR and found that IUGR, hyperoxia, and the combination of IUGR with hyperoxia (IUGR/hyperoxia) produced distinct changes in gene expression. IUGR in isolation demonstrated the fewest differentially expressed genes compared to control. In contrast, we detected several gene alterations in IUGR/hyperoxia; genes involved in myelination were strikingly downregulated. We also identified changes to specific regulators including TCF7L2, BDNF, SOX2, and DGCR8, through Ingenuity Pathway Analysis, that may contribute to impaired myelination in IUGR/hyperoxia. Our findings show that IUGR with hyperoxia induces unique transcriptional changes in the developing brain. These indicate mechanisms for increased risk for WMI in IUGR infants exposed to oxygen and suggest potential therapeutic targets to improve motor outcomes.Significance StatementThis study demonstrates that perinatal exposures of IUGR and/or postnatal hyperoxia result in distinct transcriptomic changes in the developing brain. In particular, we found that genes involved in normal developmental myelination, myelin maintenance, and remyelination were most dysregulated when IUGR was combined with hyperoxia. Understanding how multiple risk factors lead to WMI is the first step in developing future therapeutic interventions. Additionally, because oxygen exposure is often unavoidable after birth, an understanding of gene perturbations in this setting will increase our awareness of the need for tight control of oxygen use to minimize future motor disability.

Proposing a new approach to measuring birth size asymmetry

BACKGROUND

Existing methods of measuring birth size asymmetry based on ratios of growth parameters are clinically useful but simplistic, and as such may have limited usefulness in studies of aetiology.

OBJECTIVES

We aimed to develop a novel method of measuring asymmetric fetal growth at birth and demonstrate its utility in characterising the perturbed growth associated with a number of prenatal exposures and neonatal outcomes.

METHODS

Data were drawn from the Queensland (QLD) Perinatal Data Collection, which included all livebirths in the Australian state of QLD between July 2010 and December 2015, with analyses restricted to babies born between 32 and 42 weeks of gestation (n = 280 084). Novel measures of asymmetric birthweight, length, and head circumference were developed using a weighted average, representing "how far" an individual's given birth size measure deviated from the sample average and their other birth size measures. Associations among prenatal exposures and neonatal outcomes with the new asymmetry measures and traditional ratio measures (ie ponderal index, brain-to-body weight ratio, and birth length divided by head circumference) were then compared using log-binomial and multinomial regressions.

RESULTS

The new asymmetry measures clearly indicated that prenatal smoking was linked to a disproportionate decrease in all birth size measures and that low birthweight asymmetry and low birth head circumference asymmetry were specifically associated with neonatal respiratory distress and chromosomal abnormalities, respectively. When these same associations were tested using the traditional ratios, the estimates were weak, imprecise, and non-specific.

CONCLUSIONS

We developed a new approach to measuring fetal growth asymmetry which provides complimentary insights against the existing ratios approach. Associations with the new asymmetry measures were more precise and easier to interpret than the associations obtained using the ratios, and may better reflect the underlying pathological processes, providing an advantage when investigating the aetiologies of perturbed fetal growth.

Chest circumference in full-term newborns: how can it be predicted?

Background

Although over the years a number of studies have used chest circumference (CC) as a sensitive tool to identify the health status of infants, a particularly important aspect for this population is the lack of data on normal values and prediction equations. In order to facilitate and validate the interpretation of CC data in newborn (NB), the aim was to study the relation between CC and other anthropometric variables and develop a predictive equation for CC in a population of full-term newborns.

Methods

Cross-sectional study, carried out with full-term infants. The anthropometric (CC, head circumference - HC, length, age and weight) and hemodynamic variables were evaluated during the first 24 h of life. Bivariate analysis was performed between CC and HC, weight, length and type of delivery, followed by multiple linear regression analysis, including variables that were significant in the bivariate analysis. For data analysis, we used the SPSS program, considering p < 0.05 and 95% CI.

Results

The birth weight of the 120 NB varied between 2580 and 4225 g (mean 3360 g) and the gestational age between 37 and 42 weeks (mean 39 weeks). Approximately 61% of the sample were delivered vaginally and 67 (56%) were boys. The variables that remained statistically associated with CC after multivariate analysis were weight (β 0.003, CI: 0.002: 0.003, p = 0.001) and HC (β 0.287, CI: 0.156: 0.417, p = 0.001). For the linear regression model, the predictive equation of CC was 14.87+ (0.003 x weight) + (0.287 x HC), with a prediction of 76%.

Conclusion

The results show a positive correlation between CC and weight, length and HC, and based on the linear regression model, the predictive equation for CC is based only on weight and HC.

Maternal urinary 2-hydroxynaphthalene and birth outcomes in Taiyuan, China

BACKGROUND

Naphthalene is the simplest polycyclic aromatic hydrocarbon (PAH). It is easily emitted into the atmosphere, posing a significant risk to human health. However, limited studies have described the impact of naphthalene exposure on birth outcomes. In this study, we investigated the association between the maternal urinary metabolites of naphthalene, 2-hydroxynaphthalene (2-OH NAP), and birth outcomes.

METHOD

In the present study, four urinary PAH metabolites were measured in 263 pregnant women during late pregnancy. Multiple linear regression analysis was used to analyze the relationship between the concentrations of 2-OH NAP and birth outcomes, and restricted cubic spline models were further used to examine the shapes of the dose-response association.

RESULT

General linear models showed that prenatal urinary 2-OH NAP was associated with lower birth weight (BW) (- 4.38% for the high vs. low exposure group of 2-OH NAP; p for trend = 0.049) and higher cephalization index (CI) (4.30% for the high vs. low exposure group of 2-OH NAP; p for trend = 0.038). These associations were linear and significant when 2-OH NAP was modeled as a continuous variable in restricted cubic spline models (P _linear = 0.0293 for 2-OH NAP and BW; P _linear = 0.0326 for 2-OH NAP and CI). Multiple linear regression data indicated that each 1 ln-unit increase in 2-OH NAP was significantly associated with a 2.09 g/cm increase in the CI. The associations among 2-OH NAP, BW, and CI were also observed in a subset of participants residing close to arterial traffic.

CONCLUSION

Our data indicated that prenatal exposure to naphthalene had an adverse effect on fetal birth outcomes, especially the brain development index. Reduced exposure to naphthalene may improve newborn health outcomes. In Taiyuan, naphthalene may result from traffic pollution.

Intrauterine Growth Restriction and Hyperoxia as a Cause of White Matter Injury

Intrauterine growth restriction (IUGR) is estimated to occur in 5% of pregnancies, with placental insufficiency being the most common cause in developed countries. While it is known that white matter injury occurs in premature infants, the extent of IUGR on white matter injury is less defined in term infants. We used a novel murine model that utilizes a thromboxane A2 (TXA2) analog (U46619), a potent vasoconstrictor, to induce maternal hypertension and mimic human placental insufficiency-induced IUGR to study the white matter. We also investigated the role of hyperoxia as an additional risk factor for white matter injury, as IUGR infants are at increased risk of respiratory comorbidities leading to increased oxygen exposure. We found that TXA2 analog-induced IUGR results in white matter injury as demonstrated by altered myelin structure and changes in the oligodendroglial cell/oligodendrocyte population. In addition, our study demonstrates that hyperoxia exposure independently results in white matter perturbation. To our knowledge, this is the first study to report single and combined effects of IUGR with hyperoxia impacting the white matter and motor function. These results draw attention to the need for close monitoring of motor development in IUGR babies following hospital discharge as well as highlighting the importance of limiting, as clinically feasible, the degree of oxygen overexposure to potentially improve motor outcomes in this population of infants.

Post-discharge body weight and neurodevelopmental outcomes among very low birth weight infants in Taiwan: A nationwide cohort study

Background

Premature infants are at high risk for developmental delay and cognitive dysfunction. Besides medical conditions, growth restriction is regarded as an important risk factor for cognitive and neurodevelopmental dysfunction throughout childhood and adolescence and even into adulthood. In this study, we analyzed the relationship between post-discharge body weight and psychomotor development using a nationwide dataset.

Materials and methods

This was a nationwide cohort study conducted in Taiwan. Total of 1791 premature infants born between 2007 and 2011 with a birth weight of less than 1500 g were enrolled into this multi-center study. The data were obtained from the Taiwan Premature Infant Developmental Collaborative Study Group. The growth and neurodevelopmental evaluations were performed at corrected ages of 6, 12 and 24 months. Post-discharge failure to thrive was defined as a body weight below the 3rd percentile of the standard growth curve for Taiwanese children by the corrected age.

Results

The prevalence of failure to thrive was 15.8%, 16.9%, and 12.0% at corrected ages of 6, 12, and 24 months, respectively. At corrected ages of 24 months, 12.9% had low Mental Developmental Index (MDI) scores (MDI<70), 17.8% had low Psychomotor Developmental Index (PDI) scores (PDI<70), 12.7% had cerebral palsy, and 29.5% had neurodevelopmental impairment. Post-discharge failure to thrive was significantly associated with poor neurodevelopmental outcomes. After controlling for potential confounding factors (small for gestational age, extra-uterine growth retardation at discharge, cerebral palsy, gender, mild intraventricular hemorrhage, persistent pulmonary hypertension of newborn, respiratory distress syndrome, chronic lung disease, hemodynamic significant patent ductus arteriosus, necrotizing enterocolitis, surfactant use and indomethacin use), post-discharge failure to thrive remained a risk factor.

Conclusion

This observational study observed the association between lower body weight at corrected age of 6, 12, and 24 months and poor neurodevelopmental outcomes among VLBW premature infants. There are many adverse factors which can influence the neurodevelopment in NICU care. More studies are needed to elucidate the causal relationship.

Developmental origins of health and disease: a new approach for the identification of adults who suffered undernutrition in early life

BACKGROUND

Undernutrition in early life (UELife) is a condition associated with greater occurrence of chronic diseases in adulthood. Some studies on this relationship have used short stature as indicator of UELife. However, other non-nutritional factors can also determine short stature. Depending on the severity of UELife, the human body reacts primarily compromising weight and length gain, but prioritizing brain growth, resulting in disproportionate individuals. Based on this premise, this study aimed to validate a new anthropometric indicator of UELife.

DESIGN

Using stature and head circumference data from a probabilistic sample of 3,109 women, the Head-to-Height Index was calculated: HHI = (head × 2.898)/height. A HHI >1.028 (75th percentile) was the best cutoff for predicting obesity (best balance between sensitivity/ specificity, largest area under the receiver operating characteristic curve, and highest correlation coefficient) and was used to define the condition of body disproportionality. The strength of associations with several outcomes was tested for both disproportionality and short stature (height ≤25th percentile: 153.1 cm).

RESULTS

In adjusted analysis for confounding factors (age, smoking, and education level), the strength of the associations between body disproportionality and the analyzed outcomes was greater than that observed when short stature was used. Respectively, the observed prevalence ratios (95% CI) were (P<0.05 for all comparisons): obesity: 2.61 (2.17-3.15) vs 1.09 (0.92-1.28); abdominal obesity: 2.11 (1.86-2.40) vs 1.42 (1.27- 1.59); high blood pressure: 1.24 (1.02-1.50) vs 0.90 (0.75-1.08); hypercholesterolemia: 2.98 (1.47-6.05) vs 1.65 (0.91-2.99); and hypertriglyceridemia: 1.47 (1.07-2.03) vs 0.91 (0.69-1.21).

CONCLUSION

Body disproportionality is a more accurate indicator of UELife than short stature. While short stature may be genetically determined, a high HHI is due to metabolic adaptations to undernutrition in early life.

Ponderal index at birth associates with later risk of gestational diabetes mellitus

PURPOSE

Low birth weight (BW) and low ponderal index (PI) are associated with increased risk of type 2 diabetes mellitus. This study has two purposes: first to investigate the influence of PI on the risk of gestational diabetes mellitus (GDM); second, to study the association between glucose metabolism and BW in women with previous GDM.

METHODS

GDM cohort: 185 women with GDM in 1978-1996, attending a follow-up study in 2000-2002. Control cohort: 1137 women from a population-based diabetes screening study (Inter99) in a neighbouring county in 1999-2001. BW and birth length were collected from the original midwifery records. BW and PI were stratified into tertiles for analysis.

RESULTS

PI in the lower tertiles was associated with an increased risk of GDM [odds ratio 1.59 (95% confidence interval 1.07-2.36, p = 0.021)]. Among women with previous GDM, the area under the curve (AUC) for plasma levels of glucose and insulin during an OGTT was highest for the lower tertiles of BW (for AUCglucose p = 0.048, for AUCinsulin p = 0.047 adjusted for age and BMI).

CONCLUSIONS

Lower PI is associated with increased risk of GDM. In women with previous GDM, lower BW is associated with a more severe impairment of glucose metabolism one to two decades after the pregnancy complicated by GDM.

Cerebral Palsy-Trends in Epidemiology and Recent Development in Prenatal Mechanisms of Disease, Treatment, and Prevention

Cerebral palsy (CP) is the most common motor disability in childhood. This syndrome is the manifestation of intrauterine pathologies, intrapartum complications, and the postnatal sequel, especially among preterm neonates. A double hit model theory is proposed suggesting that an intrauterine condition along with intrapartum or postnatal insult lead to the development of CP. Recent reports demonstrated that treatment during the process of preterm birth such as magnesium sulfate and postnatal modalities such as cooling may prevent or reduce the prevalence of this syndrome. Moreover, animal models demonstrated that postnatal treatment with anti-inflammatory drugs coupled with nanoparticles may affect the course of the disease in pups with neuroinflammation. This review will describe the changes in the epidemiology of this disease, the underlying prenatal mechanisms, and possible treatments that may reduce the prevalence of CP and alter the course of the disease.

Placental examination: prognosis after delivery of the growth-restricted fetus

PURPOSE OF REVIEW

This article describes the role of placental examination in the prognostic evaluation of fetal growth restriction (FGR) infants.

RECENT FINDINGS

A new comprehensive placental classification system was reported. Maternal underperfusion, fetal thrombotic vasculopathy (FTV), villitis (including villitis of unknown etiology and infectious villitis), inflammation, and immature/dysmature villi are important factors affecting FGR prognosis, whereas genomic imprinting is a key factor affecting growth and diseases, as well as placental abnormality.

SUMMARY

We discuss the role of placental examination in determining FGR prognosis. Maternal underperfusion, fetal thrombotic vasculopathy, and villitis (including villitis of unknown etiology and infectious villitis) are the most important findings affecting FGR prognosis. Although limited, data have suggested an association of inflammation and immature/dysmature villi with postnatal growth in FGR infants. Placental size also contributes postnatally through fetal programming. In addition, placental imprinting can be a key of pre and postnatal growth and diseases, including imprinting disorders, as well as placental abnormalities such as placental mesenchymal dysplasia.

Relevant Obstetric Factors for Cerebral Palsy: From the Nationwide Obstetric Compensation System in Japan

Objective

The aim of this study was to identify the relevant obstetric factors for cerebral palsy (CP) after 33 weeks’ gestation in Japan.

Study design

This retrospective case cohort study (1:100 cases and controls) used a Japanese national CP registry. Obstetric characteristics and clinical course were compared between CP cases in the Japan Obstetric Compensation System for Cerebral Palsy database and controls in the perinatal database of the Japan Society of Obstetrics and Gynecology born as live singleton infants between 2009 and 2011 with a birth weight ≥ 2,000 g and gestation ≥ 33 weeks.

Results

One hundred and seventy-five CP cases and 17,475 controls were assessed. Major relevant single factors for CP were placental abnormalities (31%), umbilical cord abnormalities (15%), maternal complications (10%), and neonatal complications (1%). A multivariate regression model demonstrated that obstetric variables associated with CP were acute delivery due to non-reassuring fetal status (relative risk [RR]: 37.182, 95% confidence interval [CI]: 20.028–69.032), uterine rupture (RR: 24.770, 95% CI: 6.006–102.160), placental abruption (RR: 20.891, 95% CI: 11.817–36.934), and preterm labor (RR: 3.153, 95% CI: 2.024–4.911), whereas protective factors were head presentation (RR: 0.199, 95% CI: 0.088–0.450) and elective cesarean section (RR: 0.236, 95% CI: 0.067–0.828).

Conclusion

CP after 33 weeks’ gestation in the recently reported cases in Japan was strongly associated with acute delivery due to non-reassuring fetal status, uterine rupture, and placental abruption.