Fetal cranial growth trajectories are associated with growth and neurodevelopment at 2 years of age: INTERBIO-21st Fetal Study

Organophosphate Ester Flame Retardants and Plasticizers in Relation to Fetal Growth in the LIFECODES Fetal Growth Study

BACKGROUND

Organophosphate esters (OPEs), used ubiquitously as flame retardants and plasticizers in consumer products, are suspected of having developmental toxicity.

OBJECTIVES

Our study aimed to estimate associations between prenatal exposure to OPEs and fetal growth, including both ultrasound (head circumference, abdominal circumference, femur length, and estimated fetal weight) and delivery [birth weight z-score, small-for-gestational age (SGA), and large-for-gestational age (LGA)] measures of growth.

METHODS

In the LIFECODES Fetal Growth Study (2008-2018), an enriched case-cohort of 900 babies born at the small and large ends of the growth spectrum, we quantified OPE biomarkers in three urine samples per pregnant participant and abstracted ultrasound and delivery measures of fetal growth from medical records. We estimated associations between pregnancy-averaged log-transformed OPE biomarkers and repeated ultrasound measures of fetal growth using linear mixed-effects models, and delivery measures of fetal growth using linear (birth weight) and logistic (SGA and LGA) regression models.

RESULTS

Most OPE biomarkers were positively associated with at least one ultrasound measure of fetal growth, but associations with delivery measures were largely null. For example, an interquartile range (IQR; 1.31  ng / mL ) increase in bis(2-chloroethyl) phosphate concentration was associated with larger z-scores in head circumference [mean difference (difference): 0.09; 95% confidence interval (CI): 0.01, 0.17], abdominal circumference (difference: 0.10; 95% CI: 0.02, 0.18), femur length (difference: 0.11; 95% CI: 0.03, 0.19), and estimated fetal weight (difference: 0.13; 95% CI: 0.04, 0.22) but not birth weight (difference: 0.04; 95% CI: - 0.08 , 0.17). At delivery, an IQR (1.00  ng / mL ) increase in diphenyl phosphate (DPHP) concentration was associated with an SGA birth (odds ratio: 1.46; 95% CI: 1.10, 1.94).

CONCLUSIONS

In a large prospective cohort, gestational OPE exposures were associated with larger fetal size during pregnancy, but associations at delivery were null. DPHP concentrations were associated with heightened risk of an SGA birth. These findings suggest that OPE exposure may affect fetal development. https://doi.org/10.1289/EHP14647.

Fetal Growth Velocity-A Breakthrough in Intrauterine Growth Assessment?

The pursuit of assessing fetal well-being in obstetrical practice remains a central tenet, propelling ongoing endeavors to explore innovative markers and diagnostic methodologies aimed at prognosing potential perinatal adversities. Deviations from standard patterns of intrauterine growth, whether exhibiting excessive or insufficient trajectories, stand as pivotal indices hinting at underlying pathophysiological processes or heightened concurrent medical conditions. Initiatives like the Delphi consensus and the INTERGROWTH-21st project strive to refine diagnostic criteria and establish international standards for fetal growth assessment. This article aims to present the current knowledge regarding the assessment of abnormal growth, including novel methods such as growth velocity. Integrating fetal growth velocity assessment into perinatal care protocols holds promise in enhancing diagnostic precision. Growth velocity, involving changes in fetal size over a given period, offers insights into distinguishing between constitutional and pathological growth abnormalities. Various methodologies and models have been proposed to evaluate growth velocity, with notable advancements in understanding fetal growth patterns across different trimesters. It is believed that accelerated and reduced growth velocity may be a sensible parameter in the detection of fetal growth restriction (FGR), small-for-gestational-age (SGA) fetuses, large-for-gestational-age (LGA) fetuses and macrosomic fetuses as well as appropriate-for-gestational age (AGA) fetuses that encounter problems with growth continuation. Recent studies found that changes in growth velocity reflect the risk of adverse perinatal outcomes (APOs). Future directions in fetal health research aim to elucidate the long-term consequences of abnormal fetal growth velocity on neurodevelopmental outcomes, highlighting the critical role of early assessment and intervention.

Neonatal Physical Growth Predicts Electroencephalography Power in Rural South African Children

Anthropometric measures at birth, indexing prenatal growth, are associated with later cognitive development. Children in low- and middle-income countries (LMIC) are at elevated risk for impaired prenatal and early postnatal growth and enduring cognitive deficits. However, the associations of neonatal physical growth with neural activity are not well-characterized in LMIC contexts, given the dearth of early childhood neuroimaging research in these settings. The current study examined birth length, weight, and head circumference as predictors of EEG relative power over the first three years of life in rural Limpopo Province, South Africa, controlling for postnatal growth and socioeconomic status (SES). A larger head circumference at birth predicted lower relative gamma power, lower right hemisphere relative beta power, and higher relative alpha and theta power. A greater birth length also predicted lower relative gamma power. There were interactions with timepoints such that the associations of birth head circumference and length with EEG power were most pronounced at the 7-month assessment and were attenuated at the 17- and 36-month assessments. The results identify birth head circumference and length as specific predictors of infant neural activity within an under-resourced context.

Cooking with liquefied petroleum gas or biomass and fetal growth outcomes: a multi-country randomised controlled trial

BACKGROUND

Household air pollution might lead to fetal growth restriction during pregnancy. We aimed to investigate whether a liquefied petroleum gas (LPG) intervention to reduce personal exposures to household air pollution during pregnancy would alter fetal growth.

METHODS

The Household Air Pollution Intervention Network (HAPIN) trial was an open-label randomised controlled trial conducted in ten resource-limited settings across Guatemala, India, Peru, and Rwanda. Pregnant women aged 18-34 years (9-19 weeks of gestation) were randomly assigned in a 1:1 ratio to receive an LPG stove, continuous fuel delivery, and behavioural messaging or to continue usual cooking with biomass for 18 months. We conducted ultrasound assessments at baseline, 24-28 weeks of gestation (the first pregnancy visit), and 32-36 weeks of gestation (the second pregnancy visit), to measure fetal size; we monitored 24 h personal exposures to household air pollutants during these visits; and we weighed children at birth. We conducted intention-to-treat analyses to estimate differences in fetal size between the intervention and control group, and exposure-response analyses to identify associations between household air pollutants and fetal size. This trial is registered with ClinicalTrials.gov (NCT02944682).

FINDINGS

Between May 7, 2018, and Feb 29, 2020, we randomly assigned 3200 pregnant women (1593 to the intervention group and 1607 to the control group). The mean gestational age was 14·5 (SD 3·0) weeks and mean maternal age was 25·6 (4·5) years. We obtained ultrasound assessments in 3147 (98·3%) women at baseline, 3052 (95·4%) women at the first pregnancy visit, and 2962 (92·6%) at the second pregnancy visit, through to Aug 25, 2020. Intervention adherence was high (the median proportion of days with biomass stove use was 0·0%, IQR 0·0-1·6) and pregnant women in the intervention group had lower mean exposures to particulate matter with a diameter less than 2·5 μm (PM2·5; 35·0 [SD 37·2] μg/m3vs 103·3 [97·9] μg/m3) than did women in the control group. We did not find differences in averaged post-randomisation Z scores for head circumference (0·30 vs 0·39; p=0·04), abdominal circumference (0·38 vs 0·39; p=0·99), femur length (0·44 vs 0·45; p=0·73), and estimated fetal weight or birthweight (-0·13 vs -0·12; p=0·70) between the intervention and control groups. Personal exposures to household air pollutants were not associated with fetal size.

INTERPRETATION

Although an LPG cooking intervention successfully reduced personal exposure to air pollution during pregnancy, it did not affect fetal size. Our findings do not support the use of unvented liquefied petroleum gas stoves as a strategy to increase fetal growth in settings were biomass fuels are used predominantly for cooking.

FUNDING

US National Institutes of Health and Bill & Melinda Gates Foundation.

TRANSLATIONS

For the Kinyarwanda, Spanish and Tamil translations of the abstract see Supplementary Materials section.

Identifying critical windows of prenatal phenol, paraben, and pesticide exposure and child neurodevelopment: Findings from a prospective cohort study

BACKGROUND

This study aimed to investigate how exposure to a mixture of endocrine disrupting chemicals (EDCs) during two points in pregnancy affects early childhood neurodevelopment.

METHODS

We analyzed publicly-available data from a high-risk cohort of mothers and their children (2007-2014) that measured six EDCs including methyl-, ethyl- and propyl parabens (MEPB, ETPB, PRPB), Bisphenol-A (BPA), 3,5,6-trichloro-2-pyridinol (TCPy), 3-phenoxybenzoic acid (3-PBA) in prenatal urine samples during the second and third trimesters. Neurodevelopmental scores were assessed using Mullen Scales of Early Learning (MSEL) at age 3. We used mean field variational Bayes for lagged kernel machine regression (MFVB-LKMR) to investigate the association between trimester-specific co-exposure to the six EDCs and MSEL scores at age 3, stratified by sex.

RESULTS

The analysis included 130 children. For females, the relationship between BPA and 3PBA with MSEL score varied between the two trimesters. In the second trimester, effect estimates for BPA were null but inversely correlated with MSEL score in the third trimester. 3PBA had a negative relationship with MSEL in the second trimester and positive correlation in the third trimester. For males, effect estimates for all EDCs were in opposing directions across trimesters. MFVB-LKMR analysis identified significant two-way interaction between EDCs for MSEL scores in both trimesters. For example, in females, the MSEL scores associated with increased exposure to TCPy were 1.75 units (95%credible interval -0.04, -3.47) lower in the 2nd trimester and 4.61 (95%CI -3.39, -5.84) lower in the third trimester when PRPB was fixed at the 75th percentile compared to when PRPB was fixed at the 25th percentile.

CONCLUSION

Our study provides evidence that timing of EDC exposure within the prenatal period may impact neurodevelopmental outcomes in children. More of these varying effects were identified among females. Future research is needed to explore EDC mixtures and the timing of exposure during pregnancy to enhance our understanding of how these chemicals impact child health.

Contribution of serum elements to blood pressure during pregnancy by impacting gut microbiota: A prospective cohort study

Exposure to environmental elements can alter gut microbiota, further affecting host health. Exploring the interrelationships among element exposure, gut microbiota and blood pressure (BP) during pregnancy, as well as the mediating roles of gut microbiota, is warranted, which holds implications for maternal and offspring health. In a prospective cohort study between 2017-2018, 733 pregnant women were included. The serum elements and gut microbiota during the second trimester were assessed, and BP was collected during the second and third trimester and before delivery. Fourteen associations were identified between serum elements and BP, including positive associations of zinc (Zn) and thallium (Tl) with systolic BP during the second trimester. Rubidium (Rb) showed a positive association with Pielou's evenness. Serum elements, such as Tl and Rb, were significantly associated with the relative abundance of bacteria and co-abundance groups (CAGs). Alpha diversity was negatively associated with BP levels and trajectories. Moreover, 15 associations between gut microbiota and BP were shown. Finally, mediation analysis confirmed that CAG2 and Pielou's evenness mediated the associations of Tl and Rb with BP, respectively. We concluded that serum elements can contribute to BP changes during pregnancy through gut microbiota, suggesting gut microbiota-targeted approach as a potential intervention.

Effect of maternal serum albumin level on birthweight and gestational age: an analysis of 39200 singleton newborns

Background

Serum albumin plays a pivotal role in regulating plasma oncotic pressure and modulating fluid distribution among various body compartments. Previous research examining the association between maternal serum albumin levels and fetal growth yielded limited and inconclusive findings. Therefore, the specific influence of serum albumin on fetal growth remains poorly understood and warrants further investigation.

Methods

A retrospective study involved 39200 women who had a singleton live birth at a tertiary-care academic medical center during the period from January 2017 to December 2020. Women were categorized into four groups according to the quartile of albumin concentration during early pregnancy: Q1 group, ≤41.0 g/L; Q2 group, 41.1-42.6 g/L; Q3 group, 42.7-44.3 g/L and Q4 group, >44.3 g/L. The main outcome measures were mid-term estimated fetal weight, birthweight and gestational age. Multivariate linear and logistic regression analysis were performed to detect the independent effect of maternal serum albumin level on fetal growth after adjusting for important confounding variables.

Results

In the crude analysis, a significant inverse correlation was found between early pregnancy maternal serum albumin levels and fetal growth status, including mid-term ultrasound measurements, mid-term estimated fetal weight, birthweight, and gestational age. After adjustment for a number of confounding factors, mid-term estimated fetal weight, birthweight, and birth height decreased significantly with increasing albumin levels. Compared to the Q2 group, the Q4 group had higher rates of preterm birth (aOR, 1.16; 95% CI, 1.01-1.34), small-for-gestational-age (aOR, 1.27; 95% CI, 1.11-1.45) and low birthweight (aOR, 1.41; 95% CI, 1.18-1.69), and lower rate of large-for-gestational-age (aOR, 0.85; 95% CI, 0.78-0.94). Moreover, to achieve the optimal neonatal outcome, women with higher early pregnancy albumin levels required a greater reduction in albumin levels in later pregnancy stages.

Conclusions

A higher maternal serum albumin level during early pregnancy was associated with poor fetal growth, with the detrimental effects becoming apparent as early as the mid-gestation period. These findings provided vital information for clinicians to predict fetal growth status and identify cases with a high risk of adverse neonatal outcomes early on.

Normative spatiotemporal fetal brain maturation with satisfactory development at 2 years

Maturation of the human fetal brain should follow precisely scheduled structural growth and folding of the cerebral cortex for optimal postnatal function1. We present a normative digital atlas of fetal brain maturation based on a prospective international cohort of healthy pregnant women2, selected using World Health Organization recommendations for growth standards3. Their fetuses were accurately dated in the first trimester, with satisfactory growth and neurodevelopment from early pregnancy to 2 years of age4,5. The atlas was produced using 1,059 optimal quality, three-dimensional ultrasound brain volumes from 899 of the fetuses and an automated analysis pipeline6-8. The atlas corresponds structurally to published magnetic resonance images9, but with finer anatomical details in deep grey matter. The between-study site variability represented less than 8.0% of the total variance of all brain measures, supporting pooling data from the eight study sites to produce patterns of normative maturation. We have thereby generated an average representation of each cerebral hemisphere between 14 and 31 weeks' gestation with quantification of intracranial volume variability and growth patterns. Emergent asymmetries were detectable from as early as 14 weeks, with peak asymmetries in regions associated with language development and functional lateralization between 20 and 26 weeks' gestation. These patterns were validated in 1,487 three-dimensional brain volumes from 1,295 different fetuses in the same cohort. We provide a unique spatiotemporal benchmark of fetal brain maturation from a large cohort with normative postnatal growth and neurodevelopment.

[Association of maternal isolated thyroid peroxidase antibody positive in the first trimester with fetal growth]

OBJECTIVE

To investigate the association of isolated thyroid peroxidase antibody (TPOAb) positive in the first trimester with fetal growth.

METHODS

A total of 16 446 pregnant women were included in the birth cohort study, whose last menstrual period was between May 2016 and April 2019 and with singleton pregnancy. Maternal serum samples were collected when they firstly came for prenatal care in the first trimester. The pregnant women were consecutively seen and followed in the hospital and the information of pregnant women was extracted from the electronic medical information system. The pregnant women were divided into isolated TPOAb positive group (n=1 654) and euthyroid group (n=14 792). Three fetal ultrasound examinations were scheduled during the routine prenatal visits at the hospital and were performed by trained sonographers. All fetal growth indicators were quantified as gestational age- and gender- adjusted standard deviation score (Z-score) using the generalized additive models for location, scale and shape (GAMLSS). Fetal growth indicators included estimated fetal weight (EFW), abdominal circumference (AC), biparietal diameter (BPD), femur length (FL) and head circumference (HC). Fetal growth restriction (FGR) was defined as AC or EFW Z-score＜3rd centile based on clinical consensus. Generalized estimating equation (GEE) analysis was applied to assess the association of maternal isolated TPOAb positive with fetal growth. The generalized linear model was further used to analyze the association between isolated TPOAb positive and fetal growth indicator at different gestational ages when the fetal growth indicator was significantly associated with isolated TPOAb positive in the GEE mo-del.

RESULTS

The median gestational age at three ultrasound measurements was 23.6 (23.3, 24.1), 30.3 (29.7, 30.9), 37.3 (37.0, 37.7) weeks, respectively. The BPD Z-score was higher in isolated TPOAb positive women, compared with the euthyroid pregnant women after adjustment (β=0.057, 95%CI: 0.014-0.100, P=0.009). The generalized linear model showed the BPD Z-score was higher in the isolated TPOAb positive women at the end of 21-25 weeks (β=0.052, 95%CI: 0.001-0.103, P=0.044), 29-32 weeks (β=0.055, 95%CI: 0.004-0.107, P=0.035) and 36-40 weeks (β=0.068, 95%CI: 0.011-0.125, P=0.020), compared with the euthyroid pregnant women. There was no difference in other fetal growth indicators (EFW, AC, FL and HC) and FGR between the isolated TPOAb positive and euthyroid pregnant women.

CONCLUSION

The BPD Z-score was slightly increased in the isolated TPOAb positive pregnant women in the first trimester, while other fetal growth indicators were not changed. The reproducibility and practical significance of this result need to be confirmed.

Association between maternal haemoglobin concentrations and maternal and neonatal outcomes: the prospective, observational, multinational, INTERBIO-21st fetal study

BACKGROUND

Anaemia in pregnancy is a global health problem with associated maternal and neonatal morbidity and mortality. We aimed to investigate the association between maternal haemoglobin concentrations during pregnancy and the risk of adverse maternal and neonatal outcomes.

METHODS

In this prospective, observational, multinational, INTERBIO-21st fetal study conducted at maternity units in Brazil, Kenya, Pakistan, South Africa, and the UK, we enrolled pregnant women (aged ≥18 years, BMI <35 kg/m2, natural conception, and singleton pregnancy) who initiated antenatal care before 14 weeks' gestation. At each 5±1 weekly visit until delivery, information was collected about the pregnancy, as well as the results of blood tests taken as part of routine antenatal care, including haemoglobin values. The outcome measures were maternal (gestational diabetes, pregnancy-induced hypertension, and preterm premature rupture of membranes) and neonatal outcomes (small for gestational age, preterm birth, and acute respiratory distress syndrome).

FINDINGS

Between Feb 8, 2012, and Nov 30, 2019, 2069 women (mean age 30·7 years [SD 5·0]) had at least one routinely haemoglobin concentration measured at 14-40 weeks' gestation, contributing 4690 haemoglobin measurements for the analysis. Compared with a haemoglobin cutoff of 110 g/L, the risk was increased more than two-fold for pregnancy-induced hypertension at haemoglobin concentrations of 170 g/L (risk ratio [RR] 2·29 [95% CI 1·19-4·39]) and higher, for preterm birth at haemoglobin concentrations of 70 g/L (RR 2·04 [95% CI 1·20-3·48]) and 165 g/L (RR 2·06 [95% CI 1·41-3·02]), and for acute respiratory distress syndrome at haemoglobin concentrations of 165 g/L (RR 2·84 [95% CI 1·51-5·35]). Trimester-specific results are also presented.

INTERPRETATION

Our data suggests that the current WHO haemoglobin cutoffs are associated with reduced risk of adverse maternal and neonatal outcomes. The current haemoglobin concentration cutoffs during pregnancy should not only consider thresholds for low haemoglobin concentrations that are associated with adverse outcomes but also define a threshold for high haemoglobin concentrations given the U-shaped relationship between haemoglobin concentration and adverse neonatal and maternal outcomes.

FUNDING

Bill & Melinda Gates Foundation.

Application and Progress of Artificial Intelligence in Fetal Ultrasound

Prenatal ultrasonography is the most crucial imaging modality during pregnancy. However, problems such as high fetal mobility, excessive maternal abdominal wall thickness, and inter-observer variability limit the development of traditional ultrasound in clinical applications. The combination of artificial intelligence (AI) and obstetric ultrasound may help optimize fetal ultrasound examination by shortening the examination time, reducing the physician's workload, and improving diagnostic accuracy. AI has been successfully applied to automatic fetal ultrasound standard plane detection, biometric parameter measurement, and disease diagnosis to facilitate conventional imaging approaches. In this review, we attempt to thoroughly review the applications and advantages of AI in prenatal fetal ultrasound and discuss the challenges and promises of this new field.

Application of multilevel linear spline models for analysis of growth trajectories in a cohort with repeat antenatal and postnatal measures of growth: a prospective cohort study

OBJECTIVES

To model trajectories of antenatal and postnatal growth using linear spline multilevel models.

DESIGN

Prospective cohort study.

SETTING

Maternity hospital in Dublin, Ireland.

PARTICIPANTS

720-759 mother-child pairs from the ROLO study (initially a randomised control trial of a low glycaemic index diet in pregnancy to prevent recurrence of macrosomia [birth weight >4 kg]).

PRIMARY OUTCOMES

Trajectories of growth from 20 weeks gestation (abdominal circumference [AC], head circumference [HC] and weight) or birth (length/height) to 5 years.

RESULTS

Over 50% of women had third-level education and 90% were of white ethnicity. Women were a mean (SD) age of 32 years (4.2) at recruitment. The best fitting model for AC, HC and weight included a model with 5 linear spline periods. The best fitting models for length/height included a model with 3 linear spline periods from birth to 6 months, 6 months to 2 years and 2 years to 5 years. Comparison of observed and predicted values for each model demonstrated good model fit. For all growth measures, growth rates were generally fastest in pregnancy or immediately post partum (for length/height), with rates of growth slowing after birth and becoming slower still as infancy and childhood progressed.

CONCLUSION

We demonstrate the application of multilevel linear spline models for examining growth trajectories when both antenatal and postnatal measures of growth are available. The approach may be useful for cohort studies or randomised control trials with repeat prospective assessments of growth.

Machine learning for accurate estimation of fetal gestational age based on ultrasound images

Accurate estimation of gestational age is an essential component of good obstetric care and informs clinical decision-making throughout pregnancy. As the date of the last menstrual period is often unknown or uncertain, ultrasound measurement of fetal size is currently the best method for estimating gestational age. The calculation assumes an average fetal size at each gestational age. The method is accurate in the first trimester, but less so in the second and third trimesters as growth deviates from the average and variation in fetal size increases. Consequently, fetal ultrasound late in pregnancy has a wide margin of error of at least ±2 weeks' gestation. Here, we utilise state-of-the-art machine learning methods to estimate gestational age using only image analysis of standard ultrasound planes, without any measurement information. The machine learning model is based on ultrasound images from two independent datasets: one for training and internal validation, and another for external validation. During validation, the model was blinded to the ground truth of gestational age (based on a reliable last menstrual period date and confirmatory first-trimester fetal crown rump length). We show that this approach compensates for increases in size variation and is even accurate in cases of intrauterine growth restriction. Our best machine-learning based model estimates gestational age with a mean absolute error of 3.0 (95% CI, 2.9-3.2) and 4.3 (95% CI, 4.1-4.5) days in the second and third trimesters, respectively, which outperforms current ultrasound-based clinical biometry at these gestational ages. Our method for dating the pregnancy in the second and third trimesters is, therefore, more accurate than published methods.

Ambient temperature during pregnancy and fetal growth in Eastern Massachusetts, USA

Background

Left unabated, rising temperatures pose an escalating threat to human health. The potential effects of hot temperatures on fetal health have been under-explored. Here, we examined the association between prenatal ambient temperature exposure and fetal growth measures in a Massachusetts-based pregnancy cohort.

Methods

We used ultrasound measurements of biparietal diameter (BPD), head circumference (HC), femur length and abdominal circumference (AC), in addition to birthweight (BW), from 9446 births at Beth Israel Deaconess Medical Center from 2011 to 2016. Ultrasound scans were classified into three distinct gestational periods: 16–23 weeks, 24–31 weeks, 32+ weeks; and z-scores were created for each fetal growth measure using the INTERGROWTH-21st standards. We fitted distributed lag models to estimate the time-varying association between weekly temperature and fetal growth, adjusting for sociodemographic characteristics, seasonal and long-term trends, humidity and particulate matter (PM2.5).

Results

Higher ambient temperature was associated with smaller fetal growth measures. The critical window of exposure appeared to be Weeks 1–20 for ultrasound parameters, and high temperatures throughout pregnancy were important for BW. Associations were strongest for head parameters (BPD and HC) in early to mid-pregnancy, AC late in pregnancy and BW. For example, a 5ºC higher cumulative temperature exposure was associated with a lower mean AC z-score of -0.26 (95% CI: -0.48, -0.04) among 24–31-Week scans, and a lower mean BW z-score of -0.32 (95% CI: -0.51, -0.12).

Conclusion

Higher temperatures were associated with impaired fetal growth. This has major health implications given that extreme temperatures are more common and escalating.

Preeclampsia prediction with blood pressure measurements: A global external validation of the ALSPAC models

OBJECTIVE

The prediction of preeclampsia in pregnancy has resulted in a plethora of prognostic models. Yet, very few make it past the development stage and most fail to influence clinical practice. The timely identification of high-risk pregnant women could deliver a tailored antenatal care regimen, particularly in low-resource settings. This study externally validated and calibrated previously published models that predicted the risk of preeclampsia, based on blood pressure (BP) at multiple time points in pregnancy, in a geographically diverse population.

METHODS

The prospective INTERBIO-21st Fetal Study included 3,391 singleton pregnancies from Brazil, Kenya, Pakistan, South Africa, Thailand and the UK, 2012-2018. Preeclampsia prediction was based on baseline characteristics, BP and deviation from the expected BP trajectory at multiple time points in pregnancy. The prediction rules from the Avon Longitudinal Study of Parents and Children (ALSPAC) were implemented in the INTERBIO-21st cohort.

RESULTS

Model discrimination was similar to the development cohort. Performance was best with baseline characteristics and a BP measurement at 34 weeks' gestation (AUC 0.85, 95 % CI 0.80-0.90). The ALSPAC models largely overestimated the true risk of preeclampsia incidence in the INTERBIO-21st cohort.

CONCLUSIONS

After recalibration, these prediction models could potentially serve as a risk stratifying tool to help identify women who might benefit from increased surveillance during pregnancy.

Association between fetal abdominal growth trajectories, maternal metabolite signatures early in pregnancy, and childhood growth and adiposity: prospective observational multinational INTERBIO-21st fetal study

BACKGROUND

Obesity predominantly affects populations in high-income countries and those countries facing epidemiological transition. The risk of childhood obesity is increased among infants who had overweight or obesity at birth, but in low-resource settings one in five infants are born small for gestational age. We aimed to study the relationships between: (1) maternal metabolite signatures; (2) fetal abdominal growth; and (3) postnatal growth, adiposity, and neurodevelopment.

METHODS

In the prospective, multinational, observational INTERBIO-21st fetal study, conducted in maternity units in Pelotas (Brazil), Nairobi (Kenya), Karachi (Pakistan), Soweto (South Africa), Mae Sot (Thailand), and Oxford (UK), we enrolled women (≥18 years, with a BMI of less than 35 kg/m², natural conception, and a singleton pregnancy) who initiated antenatal care before 14 weeks' gestation. Ultrasound scans were performed every 5±1 weeks until delivery to measure fetal growth and feto-placental blood flow, and we used finite mixture models to derive growth trajectories of abdominal circumference. The infants' health, growth, and development were monitored from birth to age 2 years. Early pregnancy maternal blood and umbilical cord venous blood samples were collected for untargeted metabolomic analysis.

FINDINGS

From Feb 8, 2012, to Nov 30, 2019, we enrolled 3598 pregnant women and followed up their infants to 2 years of age. We identified four ultrasound-derived trajectories of fetal abdominal circumference growth that accelerated or decelerated within a crucial 20-25 week gestational age window: faltering growth, early accelerating growth, late accelerating growth, and median growth tracking. These distinct phenotypes had matching feto-placental blood flow patterns throughout pregnancy, and different growth, adiposity, vision, and neurodevelopment outcomes in early childhood. There were 709 maternal metabolites with positive effect for the faltering growth phenotype and 54 for the early accelerating growth phenotype; 31 maternal metabolites had a negative effect for the faltering growth phenotype and 76 for the early accelerating growth phenotype. Metabolites associated with the faltering growth phenotype had statistically significant odds ratios close to 1·5 (ie, suggesting upregulation of metabolic pathways of impaired fetal growth). The metabolites had a reciprocal relationship with the early accelerating growth phenotype, with statistically significant odds ratios close to 0.6 (ie, suggesting downregulation of fetal growth acceleration). The maternal metabolite signatures included 5-hydroxy-eicosatetraenoic acid, and 11 phosphatidylcholines linked to oxylipin or saturated fatty acid sidechains. The fungicide, chlorothalonil, was highly abundant in the early accelerating growth phenotype group.

INTERPRETATION

Early pregnancy lipid biology associated with fetal abdominal growth trajectories is an indicator of patterns of growth, adiposity, vision, and neurodevelopment up to the age of 2 years. Our findings could contribute to the earlier identification of infants at risk of obesity.

FUNDING

Bill & Melinda Gates Foundation.

Detected prenatal perfluorooctanoic acid (PFOA) exposure is associated with decreased fetal head biometric parameters in participants experiencing higher perceived stress during pregnancy in the MADRES cohort

BACKGROUND

Perfluoroalkyl substances (PFAS) are ubiquitous synthetic chemicals with long half-lives and are known to cross the placenta during pregnancy. We examined the influence of maternal PFAS levels on in utero fetal growth trajectories and assessed whether maternal stress modified these associations.

METHODS

Blood serum concentrations of five PFAS (PFOS, PFHxS, PFNA, PFOA, PFDA) were measured in 335 prenatal specimens (mean gestational age (GA): 21±9 weeks) in the MADRES cohort. Fetal growth outcomes (head circumference (HC), abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW)) were abstracted from ultrasound medical records and measured at the 3rd trimester study visit (N = 833 scans, GA range 10-42 weeks, mean 2.4 scans/participant). Adjusted linear mixed models with a GA quadratic growth curve were used for each PFAS exposure and growth outcome. PFOS and PFHxS were modeled continuously (100% sample detection), while PFOA, PFNA, and PFDA were modeled categorically (57-70% sample detection). Scores on the Perceived Stress Scale (PSS) measured in pregnancy were dichotomized at the median (<13 vs. ≥ 13) in stratified models.

RESULTS

Participants were on average 29±6 years old and predominately Hispanic (76%). Median serum concentrations of PFOS, PFHxS, PFNA, PFOA and PFDA were 1.34, 1.10, 0.07, 0.12, and 0.04 ng/mL, respectively. Participants with detected PFOA concentrations had fetuses with -2.5 mm (95% CI -4.2, -0.8) smaller HC and-0.7 mm (95% CI -1.3, -0.2) smaller BPD on average for a fixed GA than those without detected PFOA concentrations. In models stratified by PSS level, the effects of PFOA on fetal growth parameters were stronger and only significant in participants with higher stress levels (HC: β= -3.5, 95% CI -5.8, -1.4; BPD: β = -0.8, 95% CI -1.6, -1.1).

CONCLUSIONS

Prenatal PFOA exposure adversely impacted fetal head biometric parameters in participants experiencing higher stress during pregnancy.

High-risk Growth Trajectory Related to Childhood Overweight/Obesity and Its Predictive Model at Birth

CONTEXT

Childhood obesity increases the risk of chronic disease in adulthood.

OBJECTIVE

To construct an early predictive model for a growth trajectory that is highly related to childhood overweight/obesity.

DESIGN

Prospective cohort study.

SETTINGS

Shanghai Birth Cohort (SBC) and US Collaborative Perinatal Project (CPP).

PARTICIPANTS

A total of 848 mother-child pairs in the SBC (2013-2016) and 22 691 pairs in the CPP (1959-1965) with 2- and 7-year follow-up, respectively.

MAIN OUTCOME MEASURES

A high-risk postnatal growth trajectory intimately associated with childhood overweight/obesity and its predictive model.

RESULTS

We demonstrated that the shifts of postnatal body mass index (BMI) percentile had been completed around 1 year of age and identified a high-risk growth trajectory that was closely related to overweight/obesity [odds ratio 6.5 (95% CI 5.9, 7.2)] at 7 years old. Children with this trajectory presented with a consistent BMI around the 85th percentile after the age of 1 year. It could be recognized early after birth using a predictive model with 4 metabolites (tyrosine, glycine, octenoylcarnitine, and stearoylcarnitine), combined with sex, birth weight, and maternal prepregnancy BMI. The model had an area under the receiver operating characteristic curve of 0.869 (95% CI 0.779, 0.932), a sensitivity of 83.3% (95% CI 51.6%, 97.9%), and a specificity of 81.1% (95% CI 70.3%, 89.3%) in the validation data set.

CONCLUSION

Children with postnatal high-risk growth trajectories were significantly associated with subsequent overweight/obesity at 7 years old. Metabolite profiles at birth combined with clinical measures were able to predict at-risk children before overweight/obesity occurrence.

Prenatal exposure to trans fatty acids and head growth in fetal life and childhood: triangulating confounder-adjustment and instrumental variable approaches

Dietary trans fatty acids (TFAs) are primarily industrially produced and remain abundant in processed food, particularly in low- and middle-income countries. Although TFAs are a cause of adverse cardiometabolic outcomes, little is known about exposure to TFAs in relation to brain development. We aimed to investigate the effect of maternal TFA concentration during pregnancy on offspring head growth in utero and during childhood. In a prospective population-based study in Rotterdam, the Netherlands, with 6900 mother–child dyads, maternal plasma TFA concentration was assessed using gas chromatography in mid-gestation. Offspring head circumference (HC) was measured in the second and third trimesters using ultrasonography; childhood brain morphology was assessed using magnetic resonance imaging at age 10 years. We performed regression analyses adjusting for sociodemographic and lifestyle confounders and instrumental variable (IV) analyses. Our IV analysis leveraged a national policy change that led to a substantial reduction in TFA and occurred mid-recruitment. After adjusting for covariates, maternal TFA concentration during pregnancy was inversely related to fetal HC in the third trimester (mean difference per 1% wt:wt increase: − 0.33, 95% CI − 0.51, − 0.15, cm) and to fetal HC growth from the second to the third trimester (− 0.04, 95% CI − 0.06, − 0.02, cm/week). Consistent findings were obtained with IV analyses, strengthening a causal interpretation. Association between prenatal TFA exposure and HC in the second trimester or global brain volume at age 10 years was inconclusive. Our findings are of important public health relevance as TFA levels in food remain high in many countries.

The Relationship Between Fetal Growth and Retinal Nerve Fiber Layer Thickness in a Cohort of Young Adults

Purpose

To explore relationships between patterns of fetal anthropometric growth, as reflective of fetal wellbeing, and global retinal nerve fiber layer (RNFL) thickness measured in young adulthood.

Methods

Participants (n = 481) from within a Western Australian pregnancy cohort study underwent five serial ultrasound scans during gestation, with fetal biometry measured at each scan. Optic disc parameters were measured via spectral-domain optical coherence tomography imaging at a 20-year follow-up eye examination. Generalized estimating equations were used to evaluate differences in global RNFL thickness between groups of participants who had undergone similar growth trajectories based on fetal head circumference (FHC), abdominal circumference (FAC), femur length (FFL), and estimated fetal weight (EFW).

Results

Participants with consistently large FHCs throughout gestation had significantly thicker global RNFLs than those with any other pattern of FHC growth (P = 0.023), even after adjustment for potential confounders (P = 0.037). Based on model fit statistics, FHC growth trajectory was a better predictor of global RNFL thickness than birth weight or head circumference at birth. RNFL thickness did not vary significantly between groups of participants with different growth trajectories based on FAC, FFL, or EFW.

Conclusions

FHC growth is associated with RNFL thickness in young adulthood and, moreover, is a better predictor than either birth weight or head circumference at birth.

Translational Relevance

This research demonstrates an association between intrauterine growth and long-term optic nerve health, providing a basis for further exploring the extent of the influence of fetal wellbeing on clinical conditions linked to RNFL thinning.

Prenatal neonicotinoid insecticides Exposure, oxidative Stress, and birth outcomes

BACKGROUND

An increasing number of studies have reported neonicotinoid insecticides (NEOs), the emerging alternatives to conventional insecticides, may increase oxidative stress and cause adverse health effects, but limited is known about the prenatal NEOs exposures and their impact on birth outcomes.

OBJECTIVES

We investigated the levels of prenatal exposure to NEOs/metabolites, to assess their associations with birth outcomes, and investigate whether these associations could be mediated by oxidative stress using 8-OHdG as the biomarker.

METHODS

We studied 296 mother-infant pairs recruited from Laizhou Wan Birth Cohort in 2010 - 2013. Two NEOs (IMI and ACE), three metabolites (6-CN, ND-ACE, and 2CTCA), and 8-OHdG were measured in maternal urine collected before delivery. Birth outcomes including birth weight, birth length, ponderal index (PI), head circumference, and gestational age, were acquired. We examined the associations between NEOs/metabolites and birth outcomes using multivariable linear regression. Mediation analysis was conducted to clarify the role of 8-OHdG on the association of NEOs/metabolites exposure and birth outcomes.

RESULTS

Highest detection rate was observed for ACE (100.0%), followed by IMI (98.3%) and 6-CN (98.0%), suggesting the common exposure of pregnant women. The highest median concentration was observed for 6-CN with creatinine-adjusted median levels of 9.58 μg/g creatinine. A decrease in newborns' head circumference was observed with a 10-fold increase in IMI (β = -1.83; 95% CI = -3.04, -0.62) and ACE (β = -2.27; 95% CI = -3.56, -0.98). An increase in newborns' PI was observed with a 10-fold increase in IMI (β = 0.40; 95% CI = 0.03, 0.75). Maternal 8-OHdG demonstrated 38.5-65.5% mediating effects in the negative association of IMI, ACE, 2-CTCA with head circumference. These associations might differ between boys and girls.

CONCLUSIONS

Pregnant women were widely exposed to NEOs/metabolites in China. Results suggested the potential impacts of prenatal exposure to certain neonicotinoid insecticides on head circumference. Urinary 8-OHdG may partly mediate these associations.

Complex Perinatal Syndromes Affecting Early Human Growth and Development: Issues to Consider to Understand Their Aetiology and Postnatal Effects

Complex perinatal syndromes (CPS) affecting pregnancy and childhood, such as preterm birth, and intra- and extra-uterine growth restriction, have multiple, diverse contexts of complexity and interaction that determine the short- and long-term growth, health and development of all human beings. Early in life, genetically-guided somatic and cerebral development occurs alongside a psychism "in statu nascendi," with the neural structures subjected to the effects of the intra- and extra-uterine environments in preparation for optimal postnatal functioning. Different trajectories of fetal cranial and abdominal growth have been identified before 25 weeks' gestation, tracking differential growth and neurodevelopment at 2 years of age. Similarly, critical time-windows exist in the first 5-8 months of postnatal life because of interactions between the newborn and their environment, mother/care-givers and feeding practices. Understanding these complex relational processes requires abandoning classical, linear and mechanistic interpretations that are placed in rigid, artificial biological silos. Instead, we need to conduct longitudinal, interdisciplinary research and integrate the resulting new knowledge into clinical practice. An ecological-systemic approach is required to understand early human growth and development, based on a dynamic multidimensional process from the molecular or genomic level to the socio-economic-environmental context. For this, we need theoretical and methodological tools that permit a global understanding of CPS, delineating temporal trajectories and their conditioning factors, updated by the incorporation of new scientific discoveries. The potential to optimize human growth and development across chronological age and geographical locations - by implementing interventions or "treatments" during periods of greatest instability or vulnerability - should be recognized. Hence, it is imperative to take a holistic view of reproductive and perinatal issues, acknowledging at all levels the complexity and interactions of CPS and their sensitive periods, laying the foundations for further improvements in growth and development of populations, to maximize global human potential. We discuss here conceptual issues that should be considered for the development and implementation of such a strategy aimed at addressing the perinatal health problems of the new millenium.

Prenatal Exposure to Per- and Polyfluoroalkyl Substances and Child Growth Trajectories in the First Two Years

BACKGROUND

Pregnant women are ubiquitously exposed to per- and polyfluoroalkyl substances (PFAS). Prenatal exposure to PFAS has been associated with lower birth weight but also with excess adiposity and higher weight in childhood. These mixed findings warrant investigation of the relationship between PFAS and dynamic offspring growth.

OBJECTIVES

To investigate the association between prenatal PFAS exposure and early-life growth trajectories during the first 2 y.

METHODS

Pregnant women (n=3,426) were recruited from 2013 to 2016 from the Shanghai Birth Cohort (SBC) Study, and their children were followed up from birth to 2 y of age. Seven PFAS congeners were quantified in pregnant women's serum during the first trimester. Our study population was restricted to 1,350 children who had five repeated measurements for at least one anthropometric measure. Four anthropometric measures, including weight, length/height, weight-for-length, and head circumference, were evaluated at birth, 42 d, 6 months, 12 months, and 24 months, and standardized into z-scores using the World Health Organization reference. Trajectories of each measure were classified into five groups using group-based trajectory modeling. Multinomial logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) for trajectory groups according to log2-transformed PFAS concentrations, and the moderate-stable group was selected as the reference group for all measures.

RESULTS

Higher prenatal exposure to PFAS was associated with elevated odds for the low-rising weight-for-age z-score (WAZ) trajectory, and the high-rising length-for-age z-score (LAZ) trajectory. Meanwhile, PFAS levels were associated with decreased odds for the low-rising and high-rising weight-for-length z-score (WLZ) trajectories. In addition, the associations of PFAS with growth trajectory groups differed by sex, where males had greater odds for the low-rising and low-stable WAZ trajectories and for the high-stable and low-rising WLZ trajectories. In contrast, inverse associations were consistently observed with trajectories of the high-stable, low-stable, and low-rising head-circumference-for-age z-score (HCZ) in relation to most individual PFAS congeners. PFAS mixtures analysis further confirmed the above findings.

DISCUSSION

Trajectory analysis approach provided insight into the complex associations between PFAS exposure and offspring growth. Future studies are warranted to confirm the present findings with trajectory modeling strategies and understand the clinical significance of these trajectory groups. https://doi.org/10.1289/EHP9875.

Exposure to PM2.5 during Pregnancy and Fetal Growth in Eastern Massachusetts, USA

BACKGROUND

Prior studies have examined the association between fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] and fetal growth with either limited spatial or temporal resolution.

OBJECTIVES

In this study, we examined the association between PM2.5 exposure during pregnancy and fetal growth measures (ultrasound parameters and birth weight) in a pregnancy cohort using spatiotemporally resolved PM2.5 in Eastern Massachusetts, USA.

METHODS

We used ultrasound measures of biparietal diameter (BPD), head circumference, femur length, and abdominal circumference (AC), in addition to birth weight, from 9,446 pregnancies that were delivered at the Beth Israel Deaconess Medical Center from 2011-2016. We used linear mixed-effects models to examine the associations of PM2.5 in two exposure windows (the first 16 wk of pregnancy and the cumulative exposure up until the assessment of fetal growth) with anatomic scans (ultrasound measures at<24 wk), growth scans (ultrasound measures at≥24wk), and birth weight. All models were adjusted for sociodemographic characteristics, long-term trends, and temperature.

RESULTS

Higher PM2.5 exposure in the first 16 wk was associated with smaller fetal growth measures, where associations were particularly strong for BPD, AC, and birth weight. For example, a 5-μg/m3 increase in PM2.5 was associated with a lower mean BPD z-score of -0.19 (95% CI: -0.31, -0.06) before 24 wk, a lower mean AC z-score of -0.15 (95% CI: -0.28, -0.01) after 24 wk, and a lower mean birth weight z-score of -0.11 (95% CI: -0.20, -0.01). Analyses examining the associations with cumulative PM2.5 exposure up until the assessment of fetal growth produced attenuated associations.

CONCLUSIONS

Higher gestational exposure to PM2.5 was associated with smaller fetal growth measures at levels below the current national standards. https://doi.org/10.1289/EHP9824.