Toddlers Showed Slightly Fewer Behavioral Problems During COVID-19 Pandemic, NIH Study Finds

Posted on September 3, 2025September 3, 2025 by Jodi Snare

Toddlers assessed during the COVID-19 pandemic had slightly fewer emotional and behavioral problems compared to children assessed before the pandemic, suggesting some toddlers may have shown resilience during this time. This finding comes from a study of over 3,000 children across the United States using data from the Environmental influences on Child Health Outcomes (ECHO) Cohort Consortium collected between September 2009 and July 2023.

The COVID-19 pandemic disrupted family patterns and children’s environments, both critical for early brain development and well-being. While earlier research raised concerns about infants born during the pandemic, there is limited information about how toddlers’ emotional and behavioral health might have been affected.

To explore this, the study examined data from 3,438 toddlers (average age of 2 years) across the U.S. and Puerto Rico. Researchers used the Preschool Child Behavior Checklist (CBCL), a parent-reported measure of child behavior and emotions, to compare children assessed before and during the pandemic.

Children were grouped based on when they were born and when their behavior was assessed: before the pandemic, born before but assessed after March 2020, or both born and assessed during the pandemic. Parents completed the CBCL, which asks about behaviors such as anxiety, sadness, and aggression. These reports helped researchers understand how growing up during the pandemic might have influenced toddler emotional and behavioral health.

Key findings include:

Children who experienced the pandemic had significantly lower scores for internalizing problems (such as anxiety and sadness) and externalizing problems (such as aggression or hyperactivity) compared to children assessed before the pandemic.

Internalizing problem scores were about 1.5 to 2 points lower, and externalizing problem scores were about 1.7 to 3.2 points lower than those born and assessed before the onset of the pandemic.

Although the differences were small, they were consistent. The associations were stronger among children whose mothers did not have a bachelor’s degree.

“Our findings suggest that even during periods of widespread pandemic-related disruption, toddler-aged children may have experienced opportunities for resilience,” said study author Anahid Akbaryan, a Research Associate at NYU Grossman School of Medicine. “Future research should explore within-home factors that may have supported child mental health outcomes during this time, such as consistent caregiving routines, household stability, and positive parental coping strategies to identify potential protective influences during times of instability.”

Study author Lauren Shuffrey, PhD, of NYU Grossman School of Medicine, added, “These findings suggest that some families may have adapted in ways that buffered young children from behavioral challenges during the pandemic, highlighting the importance of identifying and strengthening those protective supports.”

The researchers emphasized that further studies are needed to identify these protective factors and develop strategies to help families support child well-being during and after times of global disruptions.

This collaborative research is published in JAMA Network Open.

About ECHO
The ECHO Cohort Consortium is a research program supported by the National Institutes of Health (NIH) with the mission to enhance the health of children for generations to come. ECHO Cohort investigators study the effects of a broad range of early environmental influences on child health and development. For more information, visit echochildren.org.

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Exposure to Certain Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children

Posted on August 26, 2025August 26, 2025 by Jodi Snare

Exposure to certain organophosphate esters (OPEs)—chemicals commonly used as flame retardants and plastic softeners in a variety of household and industrial products—during pregnancy was associated with more behavioral issues in young children, according to a new ECHO Cohort study led by Jiwon Oh, PhD and Deborah Bennett, PhD of the University of California, Davis.

Previous research has linked exposure to OPEs during pregnancy with potential adverse effects on child brain development, but more evidence is needed. In this study, researchers investigated the association between prenatal exposure to OPEs and child behaviors. The study included 2,948 mother-child pairs from 12 ECHO Cohort study sites across the U.S., and the investigators used the Child Behavior Checklist for ages 1½–5 to assess each child’s behavior during early childhood.

Among the nine OPEs measured, diphenyl phosphate (DPHP) was detected in almost all pregnant women (99.5%) and had the highest median concentration. Other frequently detected OPEs included dibutyl phosphate/di-isobutyl phosphate (DBUP/DIBP), bis (1,3-dichloro-2-propyl) phosphate (BDCPP), bis(2-chloroethyl) phosphate (BCETP), bis(2-butoxyethyl) phosphate (BBOEP), and bis(1-chloro-2-propyl) phosphate (BCPP).

“This research builds on a growing body of evidence of potential harm caused by exposures to OPEs,” said Dr. Bennett.

Key Takeaways include:

Prenatal exposure to BBOEP (at moderate concentrations rather than high concentrations) was associated with more internalizing behaviors (e.g., anxiety, depression), externalizing behaviors (e.g., aggression, hyperactivity), and total behavior issues in young children.
Exposure to BCPP was associated with more externalizing behaviors and total behavior issues.
Detectable dipropyl phosphate (DPRP) was associated with fewer externalizing behaviors.
Boys showed more behavior issues associated with prenatal BDCPP and BCPP exposure.
Children from highly vulnerable neighborhoods—defined by community-level demographics, socioeconomic status, housing, access to transportation, and other factors—exhibited more behavior issues associated with prenatal BCPP exposure.

“While further research is needed, our findings suggest that reducing exposure to this chemical class during pregnancy may help mitigate emotional and behavioral problems in young children,” said Dr. Oh.

This collaborative research, titled “Prenatal Exposure to Organophosphate Ester Flame Retardants and Behavioral Outcomes in Early Childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort,” is published in Environment International.

Read the research summary.

Prenatal Exposure to Phthalates, But Not Alternatives, May Influence Children’s Behavior, ECHO Study Finds

Posted on August 26, 2025August 26, 2025 by Jodi Snare

Exposure to certain phthalates during pregnancy is associated with small to modest increases in behavioral issues, such as aggression and attention problems, in children aged 1.5 to 5 years, according to ECHO Cohort research led by Jiwon Oh, PhD and Deborah Bennett, PhD of the University of California Davis.

Researchers analyzed 27 phthalate and 6 alternative plasticizer metabolites in a large and diverse group of participants, exploring how these chemicals relate to both internalizing behaviors (like anxiety and depression) and externalizing behaviors (such as emotional reactivity, aggression, and attention difficulties).

The study found that higher levels of two specific phthalate metabolites—mono-benzyl phthalate (MBzP) and mono-hexyl phthalate (MHxP)—were connected to more externalizing behaviors, such as aggression or attention problems. However, these chemicals weren’t strongly linked to internalizing behaviors like anxiety or depression. The study also looked at a newer plasticizer called DINCH but didn’t find any effects on children’s behavior.

“While this study did not observe neurobehavioral impacts of the alternative plasticizer DINCH, a broader range of alternative plasticizers deserves attention due to their increasing use and potential neurotoxicity observed in laboratory studies,” said Jiwon Oh, PhD, of the University of California, Davis, who led the research.

The impact of these chemicals varied between boys and girls and depended on the neighborhood where the children lived. Some chemicals had stronger associations in kids from neighborhoods with more resources, while others were more impactful in areas with fewer resources.

These findings highlight the importance of understanding how prenatal exposure to widely used chemicals may affect early childhood behavior and underscore the need for further research on plasticizers that are used as replacements for phthalates.

This collaborative research titled “Prenatal exposure to phthalates and alternative plasticizers and emotional and behavioral outcomes in early childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort” is published in Environment International.

Read the research summary.

NIH Study Finds Association Between PFAS Exposures During Pregnancy and Changes in Maternal Gut Microbiome

Posted on August 18, 2025August 18, 2025 by Jodi Snare

Exposure to per- and polyfluoroalkyl substances (PFAS)—man-made chemicals found in a variety of consumer products and contaminated water, air, and food—during pregnancy was associated with changes in maternal gut microbiome, according to a new study funded by the National Institutes of Health (NIH) Environmental influences on Child Health Outcomes (ECHO) Program.

The composition of the gut microbiome is dependent on factors including diet, lifestyle, and exposure to environmental chemicals, and has implications for human health. “Changes in the maternal microbiome may impact multiple pregnancy health outcomes related to metabolism and inflammation, thus it is important to identify environmental factors such as PFAS that can modulate microbiome form and function,” said ECHO Cohort investigator Michael Petriello, PhD of Wayne State University.

Key takeaways include:

Prenatal PFAS exposure was significantly associated with the relative abundance of specific types of bacteria in the maternal gut microbiome.
Associations between PFAS exposure and the gut microbiome differed by study location, with some bacteria present in one location but not the other.
In both sites, prenatal PFAS exposure did not have a significant effect on the diversity of microbes in the maternal gut microbiome.

The effect of PFAS exposure on maternal gut microbiome composition may have broader implications for the health of both the mother and baby.

“It is important to decrease exposure to pollutants such as PFAS, but complementary interventions focused on improving microbiome health and resiliency may also help to decrease the toxicity of environmental chemicals,” said Dr. Petriello.

This collaborative research, titled “Prenatal PFAS exposure and outcomes related to microbiome composition and diversity in later pregnancy,” is published in Environmental Research.

Pregnancy Diet Patterns and their Associations with Birth Outcomes Differ Across Racial and Ethnic Groups

Posted on August 18, 2025August 18, 2025 by Jodi Snare

Dietary patterns during pregnancy can affect maternal blood sugar levels and birth outcomes, with important differences depending on racial and ethnic backgrounds, according to a recent ECHO Cohort study led by Luis E. Maldonado, PhD, MPH, of the University of Southern California.

Which combination of foods most influences blood sugar and birth outcomes during pregnancy remains unclear, especially across different racial and ethnic groups. Studying these differences is important because, although diet is known to affect birth outcomes, variations in dietary patterns may help explain disparities—for example, Hispanic women in the U.S. face higher rates of preterm birth and low birthweight compared to non-Hispanic White women.

“Our findings show it’s important to look at how diet affects birth outcomes in different racial and ethnic groups separately, especially in diverse communities,” said Dr. Maldonado. “Combining all racial and ethnic groups into one might hide important differences in how diet relates to birth outcomes for each group.”

Researchers analyzed data from over 980 pregnant women—420 Hispanic and 564 non-Hispanic White participants—from two ECHO Cohort study sites. Their aim was to identify how different combinations of food related to blood sugar and birth outcomes such as preterm birth and low birthweight.

Key takeaways

Diets high in refined grains (like white bread or white rice) and low in whole grains were linked to babies being born earlier, smaller, or with low birthweight.
Analyzing dietary patterns within specific racial and ethnic groups revealed stronger associations with negative birth outcomes than when looking at the combined group.
Among non-Hispanic White women, whole grains were most strongly associated with better blood sugar control.
Fruit was linked to higher blood sugar levels among Hispanic participants.
Solid fats and nuts and seeds were associated with lower blood sugar levels in both groups.

The study underscores the value of considering dietary patterns separately within racial and ethnic groups to better understand how diet affects pregnancy outcomes. Future research can build on these findings by continuing to explore culturally relevant dietary patterns in diverse populations, helping uncover associations that may be missed in broader, combined analyses.

This collaborative research, titled “Racial/Ethnic-Derived Maternal Diets Predict Birth Outcomes Better than a Diet Derived from a Combined Sample among Hispanic/Latina and non-Hispanic White Pregnant Individuals in the ECHO Cohort,” in Nutrition.

Celebrating Innovation: Meet the OIF Round 2 Principal Investigators

Posted on August 13, 2025 by Jodi Snare

The ECHO Coordinating Center is pleased to announce that the NIH ECHO Program Office selected 12 investigators to receive research funding through the ECHO Opportunities and Innovation Fund (OIF).

The OIF is an NIH-funded grant mechanism to support early career investigators who propose projects that introduce new research, tools, and technologies to the ECHO Program. Each OIF investigator is sponsored by an ECHO award.

For this OIF round, NIH requested proposals focusing on the following areas:

ECHO Cycle 2 Scientific Priorities defined by the ECHO Steering Committee
The Science of Operations, specifically:
- Return of individual research results
- Refinement of measures

Congratulations to the awardees! See below for the full list of awardees and their research proposal titles.

Jyoti Angal, PhD – Elliott Award, Avera McKennan
Examining the Impact of Returning Individual Developmental Screening Results on Opportunities for Early Intervention Access among Children in the ECHO Program
Rana Chehab, PhD, MPH, RD – Ferrara Award, Kaiser Permanente Northern California
Neighborhood Park Environment and Child Growth Trajectories and Obesity Risk: Opportunities to Identify Sensitive Windows of Exposure and Effect Modifiers
Lauren Eaves, PhD, IBCLC – O’Shea Award, University of North Carolina Chapel Hill
G-computation for Public Health Interventions: An ECHO-wide Case Study of Lead and Preterm Birth
Jason Giles, PhD – Dabelea Award, University of Colorado Denver
Implementation of a Phenome-Wide Association Study for Identifying Childhood Asthma Pleiotropy in ECHO
Lauren Hoskovec, PhD – Dabelea Award, Colorado State University
Identifying Windows of Susceptibility to Wildfire Smoke Exposure: Growth Trajectories and Mitigation
Meghan JaKa, PhD – Nguyen Award, Health Partners Institute
Describing Longitudinal Patterns in Positive Health During Childhood and Correlated Assets Using a Strength-based Research Paradigm
McKenzie K. Jancsura, PhD, RN – Slaughter Award, Ohio State University
Exploring Pregnancy Outcomes’ Influence on Childhood Cardiovascular Health (EPIC-Heart Health)
Kelsey Magee, PhD – Hipwell Award, University of Pittsburgh
Psychosocial Stress Before and During Pregnancy: Implications for Child Neurodevelopment
Daniel Mork, PhD – Wright Award, Harvard T.H. Chan School of Public Health
ECHO-wide Precision Environmental Health Analyses of Air Pollution Exposure and Birth Outcomes
Allison Sherris, PhD – Karr Award, University of Washington
Establishing an ECHO-wide Sibling Cohort
Ashley Song PhD, MPH – Lyall Award, Johns Hopkins University
Patterns of Social Determinants of Health and Environmental Exposures in Child Cognitive and Behavioral Development
Rachel Tomlinson, PhD – Coordinating Center Award, University of California, San Francisco
Precision in Childhood Executive Functioning Measurement: Advancing Efficiency of Evidence Accumulation (EEA) for Developmental Insights

Exposure to Phenols During Pregnancy Associated with Changes in Non-nutritive Suck Patterns in Infants, an Early Indicator of Brain Development

Posted on August 11, 2025August 11, 2025 by Jodi Snare

Exposure to phenols—chemicals used in a variety of consumer products and industrial processes that can disrupt hormones—during pregnancy was associated with changes in patterns of infant non-nutritive suck, according to ECHO Cohort research led by Megan Woodbury, PhD and Emily Zimmerman, PhD, CCC-SLP of Northeastern University, and Andréa Aguiar, PhD of University of Illinois Urbana-Champaign.

Non-nutritive sucking is a common behavior during infancy where a baby may suck on an object that cannot provide nutrients, such as a pacifier. Non-nutritive sucking is characterized by bursts of sucking separated by pauses to breathe. Researchers can measure the frequency, speed, and strength of non-nutritive sucking. Because sucking is a behavior present from birth that is controlled by neurons in the brainstem, it is an ideal indicator of early brain development.

During the study, researchers measured phenol exposure by analyzing phenol levels in maternal urine samples collected during pregnancy. Non-nutritive sucking was evaluated in 1- to 8-week-old infants using a custom pacifier for approximately 5 minutes.

Key takeaways include:

Exposure to Bisphenol F, a common alternative to Bisphenol A or BPA found in some food packaging, was related to a lower non-nutritive suck frequency.
Exposure to Triclosan, an antimicrobial chemical found in some soaps, was associated with a higher non-nutritive suck frequency.
Exposure to other phenols used as preservatives and industrial processes (propylparaben, 2,4-dichlorophenol, and 2,5-dichlorophenol) was associated with weaker non-nutritive suck.
Exposure to some phenols used in sunscreens and industrial processes (benzophenone-3, 2,4-dichlorophenol, and 2,5-dichlorophenol) was related to more non-nutritive suck bursts per minute.
Propylparaben, a chemical used in some preservatives, was associated with more non-nutritive sucking per burst.

Previous studies linking changes in non-nutritive suck patterns to other exposures, such as maternal pregnancy stress and prenatal phthalate exposures, have also linked these exposures with decreased cognitive function in infants. The reasons these associations occur in the body are unknown but may be linked to hormone disruption during pregnancy.

“This study provides additional evidence that exposure to phenols may be related to developmental outcomes in children, demonstrating the need for continued research into how exposures during pregnancy impact infant health and development,” said Dr. Woodbury.

This collaborative research, titled “Examining the association between prenatal Phenol exposure and infant non-nutritive suck in two ECHO Cohorts,” was published in Environmental Epidemiology.

Study Links Higher Air Pollution to Increased Childhood Asthma, Highlights Unequal Burden in Black and Urban Communities

Posted on August 4, 2025September 19, 2025 by Jodi Snare

Higher exposure to fine particulate matter, nitrogen dioxide, and ground-level ozone was associated with increased asthma incidence in children up to age 10, according to a new study funded by the Environmental influences on Child Health Outcomes (ECHO) Program at the National Institutes of Health. Notably, children living in areas with higher proportions of Black residents or higher population density faced greater pollution-related asthma risk, despite overall air quality improvements in the U.S.

“Our findings show why it’s so important to keep reducing air pollution everywhere in the U.S. They also highlight the need to understand and tackle the deeper reasons why some communities are more affected than others,” said Veronica Wang, research fellow at the Harvard T.H. Chan School of Public Health.

Key Takeaways:

Higher levels of fine particulate matter, nitrogen dioxide, and ground ozone were each linked to more new cases of asthma in early childhood.
Fine particulate matter and nitrogen dioxide posed a greater asthma risk for children living in areas with more Black residents.
Children in more densely populated neighborhoods were also at higher risk from these pollutants.
The study looked at data from over 23,000 children born between 1981 and 2021 to find out which groups are more likely to develop asthma from air pollution exposure in early childhood.

The study analyzed extensive environmental and community data, highlighting the importance of reducing harmful exposures in the most affected neighborhoods.

This collaborative research was published in Environmental Epidemiology.

Vitamin D During Pregnancy May Play a Role in Children’s Cognitive Development, ECHO Study Suggests

Posted on August 4, 2025August 4, 2025 by Jodi Snare

Higher vitamin D levels during pregnancy may be linked to better scores on cognitive tests, according to a new study by the Environmental influences on Child Health Outcomes (ECHO) Cohort.

Researchers found that children whose mothers had higher vitamin D levels while pregnant tended to perform better on cognitive tests assessing skills like problem-solving and processing new information at ages 7 to 12. However, vitamin D levels were not linked to skills based on learned knowledge, such as vocabulary. The association appeared strongest among children of Black mothers, and vitamin D levels measured earlier in pregnancy seemed most important for children’s brain development. Black people often have lower vitamin D levels because their skin has more pigment, which makes it harder for the skin to produce vitamin D from sunlight.

“Our study provides important new evidence that early pregnancy may be a critical period when vitamin D has the greatest potential to support cognitive development, said Melissa M. Melough, PhD, RD of the University of Delaware, Newark. “This highlights a key opportunity for clinicians to enhance screening and support for vitamin D supplementation before and during pregnancy. “

Vitamin D deficiency is common during pregnancy and has been linked to early brain development, but few studies have examined whether these effects continue into later childhood or differ by racial group. The researchers emphasize that while these findings add to growing evidence on the role of vitamin D in pregnancy, further studies are needed to determine the optimal dose and timing of supplementation to support cognitive development.

This collaborative research was published in The American Journal of Clinical Nutrition.

Living in Low-income-low-food-access Neighborhoods Linked to Higher Risk of Childhood Asthma

Posted on July 31, 2025July 31, 2025 by Jodi Snare

Living in a low-income neighborhood with low food access was associated with higher risks of developing asthma, according to a recent ECHO Cohort study led by Veronica A. Wang, PhD, Antonella Zanobetti, PhD, and Diane Gold, MD of Harvard T. H. Chan School of Public Health and Rima Habre, ScD of the University of Southern California.

Asthma is characterized by chronic inflammation in the lungs, and prior research shows that a nutritious diet can reduce airway inflammation. However, access to affordable and healthy foods is often difficult for many communities that have limited access to supermarkets or grocery stores. In this study, the researchers wanted to learn whether living in a low-income-low-food access neighborhood was associated with childhood asthma and whether this association was modified by sociodemographic factors.

The study included 16,012 children from 35 ECHO Cohort study sites across the U.S., and the investigators used low-income-low-food-access (LILA) neighborhood metrics from the U.S. Department of Agriculture’s Food Access Research Atlas to evaluate each child’s neighborhood food access.