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Prenatal Exposure to One Type of PFAS Linked to Small Differences in Children’s Sleep

Posted on by Jodi Snare

Children whose mothers had higher levels of one type of PFAS during pregnancy tended to have slightly more sleep problems between ages 1 and 5, according to a recent ECHO Cohort study led by Sarah D. Geiger, PhD, and Cai Zhang, of the University of Illinois Urbana-Champaign. 

Per- and polyfluoroalkyl substances, or PFAS, are long-lasting chemicals found in many consumer and industrial products. They can remain in the environment and in people’s bodies for a long time. During pregnancy, PFAS can cross the placenta, meaning a developing baby may be exposed before birth. 

Researchers studied 2,836 mother-child pairs from 14 ECHO Cohort study sites across the United States and Puerto Rico. They measured levels of four PFAS chemicals in blood samples collected during pregnancy. Caregivers later answered questions about their children’s sleep, including difficulty falling asleep, waking during the night, nightmares, and resistance at bedtime.  

Higher levels of perfluorooctanoic acid, or PFOA, during pregnancy were linked to slightly more sleep problems in young children. The pattern was similar in boys and girls. The other three PFAS chemicals studied were not clearly linked to children’s sleep problems. 

“Sleep is one of the most common concerns parents raise in early childhood, yet it is rarely studied as an outcome of prenatal chemical exposure,” said Zhang, a doctoral student at the University of Illinois Urbana-Champaign. “The difference for any one child was small, but exposure to these chemicals is widespread, so even small differences are worth continued study.” 

Future studies could examine whether prenatal PFAS exposure continues to relate to sleep as children grow older. Researchers could also study combinations of PFAS, newer replacement chemicals, and sleep measurements collected through wearable devices. 

This collaborative research, titled “Prenatal PFAS exposure and early childhood sleep quality in the ECHO Cohort,” is published in Environmental Research.  

ECHO Study Links Prenatal Exposure to Phthalate Replacement with Differences in Fetal Growth

Posted on by Jodi Snare

Higher prenatal exposure to a chemical increasingly used to replace phthalates was associated with differences in fetal growth, according to a recent ECHO Cohort study led by Leonardo Trasande, MD, MPP of NYU Langone Health.

Phthalates are widely used in food packaging, flooring, cosmetics, personal care products, and other everyday items. As manufacturers replace them with alternatives such as di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH), researchers are working to understand whether these newer chemicals may also affect maternal and child health.

ECHO researchers analyzed data from 6,617 pregnancies at 22 ECHO Cohort Study Sites. They measured three DINCH breakdown products in urine collected during pregnancy and compared exposure levels with birth weight, birth length, pregnancy length, and infant size for gestational age.

Higher levels of DINCH-related markers were associated with lower birth weight and a greater likelihood of being born small for gestational age. Associations varied by infant sex: links with birth length were stronger among boys, while links with small-for-gestational-age status were stronger among girls. Third-trimester exposure appeared more strongly associated with lower birth weight for gestational age than exposure earlier in pregnancy.

Measurable DINCH markers were common among participants, suggesting widespread exposure in this population.

Because this was an observational study, the findings cannot show that DINCH directly caused these outcomes. Additional research may help clarify how DINCH affects pregnancy and fetal development and inform evaluations of other phthalate replacements.

This collaborative research, titled “Prenatal exposure to di(isononyl) cyclohexane-1,2-dicarboxylate and adverse birth outcomes in the USA: a prospective analysis of births in a large American birth cohort,” is published in Environment International.

Adolescents Born Preterm Were Less Likely to Engage in Unhealthy Behaviors During the COVID-19 Pandemic

Posted on by Jodi Snare

Adolescents who were born preterm were less likely to report unhealthy behaviors during the COVID-19 pandemic, according to a recent ECHO Cohort study led by Michael O’Shea, MD, MPH, of the University of North Carolina, Chapel Hill.

The COVID-19 pandemic affected many adolescents’ mental health, daily routines, and social lives. Some adolescents may have been especially vulnerable, including those born preterm (<37 weeks). Previous research suggests adolescents born preterm may be less likely to take part in unhealthy behaviors, such as drinking alcohol or using marijuana.

Using data from more than 2,000 adolescents participating from 13 ECHO Cohort Study Sites across the United States, researchers compared self-reported measures of health and well-being among adolescents born at different stages of pregnancy. Participants completed surveys between March 2020 and March 2023 that assessed overall health, life satisfaction, and sense of meaning and purpose.

ECHO researchers looked at self-reported surveys from over 2,000 adolescents from thirteen ECHO Cohort Study Sites across the United States to better understand how adolescents born at different stages of pregnancy coped with the COVID-19 pandemic. Participants completed surveys about changes in healthy behaviors, unhealthy behaviors, social connection, and how the pandemic affected their lives between April 2022 and June 2022.

Compared with adolescents born at term, adolescents born preterm were less likely to say they drank alcohol, used marijuana, or took part in at least one unhealthy behavior. Healthy or prosocial behaviors were common across all adolescents included in this study. More than half of the adolescents reported doing at least one positive activity, such as spending more time with family, reading, doing puzzles, practicing mindfulness, or talking with others. Girls born preterm showed more pronounced differences in positive and unhealthy behaviors. Girls born extremely preterm (<28 weeks) were more likely to report healthy or prosocial behaviors. Adolescents born moderate or late preterm (between 28 and 37 weeks) reported feeling more socially connected during the pandemic, compared to before the pandemic, but they were also more likely to say the pandemic had a negative overall effect on their lives.

The findings of this study suggest that adolescents employed multiple strategies to cope with the psychological stressors associated with the pandemic and that adolescents born preterm, as compared to those born at term, were less likely take part in an unhealthy behavior and equally likely to take part in a healthy coping behavior.

The study authors suggest that in future national crises similar to the COVID-19 pandemic, these findings may help physicians and parents be better prepared to support adolescents, including adolescents born preterm. Additional studies could also help researchers identify counseling strategies that support healthy coping, family communication, and adolescent well-being during future pandemics, natural disasters, or other major disruptions.

This collaborative research, titled “Child health-related behaviors, social connectedness, and impact of the COVID-19 pandemic on children born preterm in the ECHO Cohort,” is published in BMC Pediatrics.

Caregivers’ Experience of Discrimination Not Significantly Linked to Child IQ Scores, ECHO Study Finds

Posted on by Jodi Snare

Caregivers’ reports of discrimination were not linked to children’s overall IQ scores, but caregiver income and education remain important factors linked to children’s brain development, according to a new ECHO Cohort study led by Jennifer Porter, MD, of the University of Louisville.

Children’s early brain development helps shape how they learn, think, and solve problems. Although average IQ scores sometimes differ across population groups, research indicates these differences are explained by differences in social, economic, and environmental conditions. One possible factor is discrimination experienced by caregivers, which may affect children through stress or changes in the home environment. However, most past studies have focused on individual or economic factors and have not fully explored how caregiver experiences with discrimination might be related to children’s cognitive development. ECHO researchers looked at data from over 1,000 children and their caregivers from eight ECHO Cohort Study Sites across the United States to better understand how caregiver discrimination and other factors may influence child brain development.

Key Takeaways include:

  • Caregivers’ reports of discrimination were not linked to children’s overall IQ scores for either Black or White children.
  • Children tended to have higher IQ scores when their caregivers had higher income and more education.
  • Neighborhood opportunity—as measured by the Child Opportunity Index that reflects neighborhood-level resources, such as access to healthy food, high-quality early childhood education, and economic opportunity—did not explain differences in children’s IQ scores after the researchers accounted for other factors.
  • Across income levels, a much higher share of Black families lived in neighborhoods with low or very low opportunity. Black caregivers also reported more discrimination overall than White caregivers.

“The study did not find a link between caregiver discrimination and child IQ, but it raises the question of how we measure discrimination,” said Dr. Porter. “The current measures may not capture the different levels of discrimination experienced by caregivers.”

Future studies could help researchers better understand the complex relationship between caregiver discrimination, other social and environmental factors, and child brain development.

This collaborative research, titled “Perceived Caregiver Discrimination and Neurocognitive Development: An Analysis from the ECHO Cohort,” is published in Journal of Racial and Ethnic Health Disparities.

Teens Born Extremely Preterm Report Positive Well-Being During the COVID-19 Pandemic

Posted on by Jodi Snare

Teens who were born extremely preterm—before 28 weeks of pregnancy—reported overall health similar to their peers born at term during the COVID-19 pandemic, according to a new ECHO Cohort study led by Elisabeth McGowan, MD, of Brown University. The findings suggest that many teens born extremely early may experience positive well-being and resilience, even during times of significant disruption.

The COVID-19 pandemic changed daily life for children and teens across the United States. School closures, reduced social activities, and changes to family routines raised concerns about how young people were coping emotionally and socially. Researchers were particularly interested in understanding how these challenges affected teens born preterm, who are often considered at greater risk for health and developmental difficulties.

Using data from more than 4,000 teens participating in the ECHO Cohort, researchers compared self-reported measures of health and well-being among teens born at different stages of pregnancy. Participants completed surveys between March 2020 and March 2023 that assessed overall health, life satisfaction, and sense of meaning and purpose.

The researchers found that teens born extremely preterm reported overall health similar to peers born at term. After accounting for demographic differences, they also reported higher life satisfaction and a stronger sense of meaning and purpose. Participants born moderately preterm or late preterm reported levels of well-being similar to those born at term.

These findings add to a growing body of research suggesting that being born very early does not necessarily lead to poorer self-reported quality of life or well-being later in life. The results also highlight the importance of asking young people directly about their experiences and perspectives rather than relying solely on medical or developmental measures.

“Positive health attributes have the potential to provide resilience and help mitigate negative exposures or experiences,” said Dr. McGowan. “By understanding characteristics that lead to resilience, particularly among high-risk groups of children, we hope to allow for identification as well as replication of strategies that help buffer against times of stress.”

McGowan noted that more studies are needed to better understand why some teens born extremely preterm report positive well-being. Future research could examine how factors such as ongoing health challenges, mental health, family support, school environments, and community resources may shape their experiences.

The study included 4,093 biological mother-child pairs from 38 ECHO Cohort Study Sites across the United States. Participants were ages 10–18 years and provided information about their health and well-being during the pandemic.

The study, “Self-reported Positive Health Outcomes During the COVID-19 Pandemic Among Adolescents Born Preterm in the ECHO Cohort,” was published in the Journal of Perinatology.

Exposure to Multiple Chemicals During Pregnancy Linked to Associated with Adverse Birth Outcomes

Posted on by Jodi Snare

Exposure to certain chemicals during pregnancy was linked to differences in gestational age and birthweight, highlighting the need to better understand the potential health effects of both well-known and less-studied chemical exposures, according to a recent ECHO Cohort study led by Jessie Buckley, PhD, MPH of UNC Chapel Hill and Tracey Woodruff, PhD, MPH of Stanford University.

Pregnant women in the United States may be exposed to dozens of chemicals at the same time, including some that are not well understood.

“We found exposures to several newer chemicals that have been used to replace toxic ones. These chemicals are not well-studied but we found that they can have similar health effects as the chemicals they replace,” said Dr. Woodruff. “This finding underscores the need to better track and evaluate new chemicals before they are introduced.”

Researchers analyzed urine samples collected from pregnant participants and detected an average of 45 chemicals out of 113 measured. The study focused on whether higher levels of these chemicals were associated with differences in birth outcomes, including gestational age, birthweight adjusted for gestational age, and risk of preterm birth or being born smaller than expected.

Key findings include:

  • Exposure to several types of chemicals was associated with differences in birth outcomes.
  • Certain phthalates (used in plastics) and polycyclic aromatic hydrocarbons (found in air pollution and some foods) were linked to shorter pregnancies or lower birthweight for gestational age.
  • Some less-studied chemicals, such as halogenated phenols, were also associated with lower birthweight for gestational age.
  • In contrast, higher levels of some insecticides and benzophenones were associated with longer gestational age or higher birthweight for gestational age.

The study included 5,318 mother–child pairs from 18 ECHO Cohort sites across the United States, with participants enrolled between 2000 and 2021. Researchers accounted for factors that can influence birth outcomes—such as maternal age, education, and tobacco use during pregnancy—to better isolate the associations between chemical exposure and outcomes.

While the observed differences in birth outcomes were small, the findings underscore how widespread chemical exposures are during pregnancy and the importance of continuing to evaluate their potential health effects.

“Our findings add to existing evidence that chemical exposures during pregnancy can worsen birth outcomes, highlighting the importance of reducing toxic chemical exposures during early life,” said Dr. Buckley.

Future research could explore whether these exposures are also linked to other child health outcomes, such as neurodevelopment, obesity, or asthma.

This collaborative research, titled “Gestational exposure to ten classes of priority chemicals and birth outcomes in the ECHO Cohort,” was published in JAMA Network Open.

New ECHO Study Finds Link Between Prenatal Air Pollution Exposure and Behavior Scores in Young Children

Posted on by Jodi Snare

Exposure to air pollutants fine particulate matter (PM2.5) and nitrogen dioxide (NO2) during pregnancy was associated with slightly higher behavior problem scores in preschool-aged children, even when PM2.5 levels were below the current United States air quality standard, according to a new ECHO Cohort study led by Jiwon Oh, PhD, and Deborah Bennett, PhD, of the University of California, Davis.

Air pollution is common in many places, and pregnant women can be exposed to it where they live, work, and travel. Scientists think some air pollutants may affect a baby’s developing brain during pregnancy, which could later show up as differences in behavior. Using data from 8,370 pregnant women and their children from 28 ECHO Cohort Study Sites across 21 U.S. states and Puerto Rico, researchers looked at the association between exposures to common air pollutants like PM2.5, NO₂, and ozone (O3) during pregnancy and behavior problems in young children.

Key takeaways:

  • Exposure to PM5 and NO2 in air pollution during pregnancy was associated with modest increases in childhood behavior problems, including externalizing behaviors (e.g., acting out, aggression, attention problems) and internalizing behaviors (e.g., anxiety, withdrawal, emotional reactivity) in preschool-aged children (1.5–5 years).
  • Exposures in different “sensitive windows” during pregnancy showed different links to child behavior. First trimester PM5 exposure was associated with higher externalizing behavior scores. Second trimester PM2.5 exposure was associated with higher internalizing behavior scores. Third trimester NO₂ exposure was linked to higher internalizing and externalizing behavior scores.
  • Ozone (O₃) exposure was not significantly associated with child behavior scores overall.
  • Certain individual and community-level sources of stress like prenatal depression and childhood neighborhood opportunity (e.g., job opportunities, economic resources, socio-economic inequities, housing quality) influenced the association between prenatal exposure to air pollution and child behavior.

“Many ECHO pregnant women are exposed to PM2.5 levels that exceed the current U.S. air quality standard,” said Dr. Bennett. “Further investigations are needed to determine whether this standard is sufficiently protective of child neurodevelopment.”

Future studies can help researchers understand if prenatal air pollution exposure continues to show an association with children’s behavior beyond early childhood. Researchers can also explore how other factors, such as stress, access to healthcare, housing conditions, and other environmental exposures, might influence the association between prenatal air pollution exposure and children’s brain development.

This collaborative research, titled “Prenatal exposure to nitrogen dioxide, fine particulates, and ozone in relation to child behavior: The Environmental influences on Child Health Outcomes (ECHO) Cohort,” was published in Environmental Science & Technology.

ECHO Study Finds No Strong Overall Link Between Exposure to Gas Stoves, Mold, or Water Damage During Pregnancy and Birth Outcomes

Posted on by Jodi Snare

Having a gas stove, mildew or mold, or water damage in the home during pregnancy was not associated with shorter pregnancy duration or lower birth weight, according to a recent ECHO Cohort study led by Deborah Bennet, PhD, and Jiwon Oh, PhD, of University of California, Davis.

While outdoor air pollution has been linked to adverse birth outcomes such as preterm birth and low birth weight, less is known about the effects of common indoor household exposures during pregnancy such as gas stoves, mold or mildew, and water damage. These exposures can contribute to indoor air pollution or damp conditions that may affect maternal and fetal health.

Overall, the results of this study found no strong overall link between these household exposures and outcomes like preterm birth or birth weight, when looking at the full study population. Using kitchen ventilation, such as a hood or fan, also did not appear to change these results.

However, some differences were seen in certain groups. For example, mold or mildew and water damage were linked to a higher likelihood of early term birth (37-38 weeks) in homes built after 1980, and mold exposure was associated with a higher chance of preterm birth among mothers with higher education. Other patterns varied by race and ethnicity.

These findings suggest that indoor air quality during pregnancy may not have a strong association with birth outcomes overall, but that housing and social factors may influence how these exposures affect health.

“Although the presence of gas stoves, mold, or water damage in the home during pregnancy was not associated with adverse birth outcomes in this population-based study, frequent ventilation through windows or doors is recommended to reduce exposure to potentially harmful indoor air pollutants,” said Dr. Bennett.

Researchers say future studies could provide more details about indoor conditions, including how often gas stoves are used, how well homes are ventilated, and how severe mold or water damage may be.

This collaborative research, titled “Prenatal Exposure to Gas Stoves, Mold, and Water Damage: Associations With Gestational Duration and Fetal Growth in the ECHO Cohort,” is published in Environmental Pollution.

Yearly Patterns of Rhinovirus Infection Consistent Over Three Decades

Posted on by Jodi Snare

Yearly circulations patterns of rhinovirus (RV)—the most common cause of the common cold—were remarkably consistent over three decades with certain types of rhinovirus found more often in infants and young children, according to a recent ECHO Cohort study led by Jo Wilson, MD of the University of Wisconsin School of Medicine and Public Health.

Some children—especially infants, toddlers, and children with asthma—can become seriously ill from a rhinovirus infection and may need hospital care. There are more than 160 different types of rhinoviruses, which has made it very difficult to develop prevention or treatment strategies. A relatively small group of rhinovirus types—about 15 to 20—account for about half of all the rhinoviruses circulating in each species, RV-A, RV-B and RV-C. Given the vast number of circulating rhinoviruses and the lack of rhinovirus surveillance programs, there has not been enough information for researchers to understand the circulation patterns of these viruses or which type are found most often in different age groups. To better understand the long‑term patterns of rhinovirus infections in children, researchers collected nearly 12,000 nasal samples from children across the United States, Finland, and Australia between 1997 and 2025.

Key Takeaways include:

  • Unlike other viruses like the flu or COVID‑19 that show dramatic changes in yearly circulation patterns, both the most common and rare rhinovirus types stayed remarkably consistent over three decades.
  • Certain rhinovirus types appeared more often in infants and young children, while a few others were common across all age groups.

The results of this study and additional studies can help researchers better understand which rhinovirus types are more commonly found in young children. This information could help guide the development of future strategies to prevent or treat rhinovirus infections.

This collaborative research, titled “Stability and Age-Specific Patterns of Rhinovirus Circulation in Children Observed Over Three Decades” is published in the Journal of Allergy and Clinical Immunology.

Perceived Stress During Pregnancy Associated with Autism-related Traits in Children

Posted on by Jodi Snare

Higher perceived stress during pregnancy may be associated with greater severity of autism-related traits in children, according to a recent ECHO Cohort study led by Luke Grosvenor, PhD, of Kaiser Permanente Northern California.

Many mothers experience higher levels of stress and other mental health challenges during pregnancy. Previous studies have found that pregnancy stress may be associated with increased risk of autism spectrum disorder (ASD) in children, but these studies have mostly focused on the occurrence of isolated adverse or stressful events that occur in the mother’s life during pregnancy. Fewer studies have measured general perceived stress among mothers during pregnancy. To better understand whether this prenatal exposure may be associated with severity of autism-related traits in children, researchers collected information from over 4,000 mothers and their children enrolled in 20 ECHO Cohort Study Sites across the United States.

Key Takeaways include:

  • Higher perceived stress during pregnancy was associated with slightly more severe autism‑related traits in children.
  • At higher prenatal perceived stress levels, children showed slightly higher scores on tests measuring social and behavioral traits related to autism. Children whose mothers had either moderate or high categorical stress scored higher than those whose mothers reported low or no stress.
  • The link between pregnancy stress and autism‑related traits did not differ between boys and girls.
  • The relationship between prenatal stress and autism‑related traits remained consistent even when the researchers accounted for mothers’ co-occurring prenatal depressive symptoms.
  • Stress during pregnancy is normal and common to experience. While the results of this study indicate that there may be a small association between pregnancy stress and autism-related traits, they do not imply that stress during pregnancy causes autism spectrum disorder or autism-related traits to occur in children.

“This study provides evidence for small yet significant associations between higher prenatal perceived stress and greater severity of autism-related traits,” said Dr. Grosvenor. “These results could have implications for prenatal mental health screening and behavioral interventions aimed at improving child outcomes.”

Future studies could help researchers better understand the specific periods during pregnancy during which stress may have the greatest association with child health and development and how other related social and emotional factors may influence this effect.

This collaborative research, titled “Associations between Prenatal Perceived Stress and Child Autism-Related Traits in the ECHO Cohort,” is published in The Journal of Pediatrics.

Read the research summary.