ECHO Study Finds Children with Autism at Higher Risk for a Range of Diverse Health Outcomes

Authors: Elizabeth Kaplan-Kahn, Kristen Lyall, Heather Volk, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Approximately 3% of children in the United States have a diagnosis of autism spectrum disorder (or autism). A large proportion of autism research focuses on understanding the factors that influence the development of autistic traits. However, many people on the autism spectrum report that they would rather prioritize research into the factors that influence their overall health and well-being. This study addresses that priority by investigating the physical, emotional, and overall health outcomes of children on the autism spectrum.

What were the study results?

This study showed that autistic children are at higher risk than non-autistic children for poorer health outcomes indicated by lowest scores in Global Health and highest dysregulation scores (e.g. attention problems, aggressive behavior, and anxious-depressive symptoms). However, there is variability in health outcomes within autistic youth as shown by a group of autistic participants who showed high scores on positive health outcomes across domains. Additionally, compared to non-autistic children, more autistic children were born prematurely, had diagnoses of intellectual disability and ADHD, and had a sibling with autism.

What was the study's impact?

The results of this study offer a glimpse into the diversity of emotional, physical, and overall health outcomes for children on the autism spectrum. A deeper understanding of the range of health outcomes children with autism experience, and the factors that can affect these outcomes, may help families and practitioners identify and target areas for support or intervention.

Who was involved?

The study included over 4,500 children and adolescents at 29 ECHO research sites across the United States, including 286 participants with autism. The participants varied in age from 5 to 20 years old.

What happened during the study?

The researchers compared the health outcomes and demographic characteristics of a large sample of children, with 286 participants with autism and 4,225 participants without. They then used a subsample of 1,809 participants, of which 116 were autistic, to group children with similar physical health, emotional health, and overall well-being outcomes into one of three categories, “positive health,” “poorer health,” and “mixed health.” These categories were mostly determined by the results of multiple Patient-Reported Outcomes Measurement Information System (PROMIS) scales and other reports that evaluated participants’ peer relations, life satisfaction, behavior dysregulation, sleep disturbances, physical activity, etc. The three profiles of participants were then further analyzed to study differences in health outcomes between children on the autism spectrum to non-autistic children.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Future work may focus on understanding the factors that influence poor or positive health for children with autism and how those factors change over time. This work might identify opportunities to support these children and promote positive health outcomes.

Where can I learn more?

Access the full journal article, titled “Describing Multidomain Health Outcomes in Autistic Children in the ECHO Program,” in the Journal of the American Academy of Child and Adolescent Psychiatry.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August 27, 2024

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ECHO Study Finds Children with Autism at Higher Risk for a Range of Diverse Health Outcomes

ECHO Cohort Study Finds No Significant Evidence that Prenatal Cannabis Exposure Increases Likelihood of Child Autism Spectrum Disorder

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ECHO Cohort Study Finds No Significant Evidence that Prenatal Cannabis Exposure Increases Likelihood of Child Autism Spectrum Disorder

Authors: Chaela Nutor, Patricia A. Brennan, et al.

Who sponsored this study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) Program, Office of The Director, National Institutes of Health.

Why was this study needed?

With the legalization of cannabis in some areas of the U.S., there has been a decrease in the perception of risk and an increase in cannabis use among pregnant women. While fetal exposure to cannabis has been linked to poorer neonatal and cognitive outcomes, relatively few studies have examined the association between prenatal cannabis exposure and neurodevelopmental outcomes, including autism spectrum disorder (ASD).

What were the study results?

The investigators found no evidence that prenatal cannabis exposure increased the likelihood for ASD in the group of children included in the study. There was also no evidence that child sex or gestational age at birth affected how prenatal cannabis exposure related to likelihood of ASD. No other aspects of brain or child development were evaluated in the study.

Note: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was this study's impact?

Although no significant associations were found with ASD outcomes in this study, other studies have found that prenatal cannabis exposure may still be associated with ASD traits or other facets of child development and behavior that were outside of the scope of this study.

Who was involved?

This study included 11,570 school-age children from 34 ECHO Cohort research sites across the U.S., including three sites that enrolled children with a higher likelihood of ASD and three sites that enrolled children from neonatal intensive care units (NICU).

What happened during the study?

ECHO Cohort researchers gathered data on cannabis use during pregnancy directly from mothers and indirectly from their medical records. They also collected information on ASD diagnosis, as well as caregiver-reported data on the children’s autism-related traits from the ages of 1 to 18 years. The researchers used this information to test whether prenatal cannabis use might be associated with ASD.

What happens next?

The researchers are planning another large national study to further examine the relationship between prenatal cannabis exposure and autism traits. Other work could examine whether exposure to cannabis in utero alters brain functioning.

Where can I learn more?

Access the full journal article, titled “Examining the Association Between Prenatal Cannabis Exposure and Child Autism Behaviors: A Multi-cohort Investigation in the Environmental influences on Child Health Outcomes (ECHO) Program," in Autism Research.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August 2024

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ECHO Cohort Study Finds No Significant Evidence that Prenatal Cannabis Exposure Increases Likelihood of Child Autism Spectrum Disorder

New ECHO Cohort Research Suggests No Significant Association Between Prenatal Cannabis Exposure and Child Autism-Related Outcomes

Posted on August 27, 2024March 31, 2025 by Jodi Snare

Collaborative ECHO research led by Chaela Nutor, MA and Patricia A. Brennan, PhD of Emory University investigates the association between prenatal cannabis exposure and autism spectrum disorder (ASD). The study looked at data from 11,570 school-aged children from across the United States and found no evidence that prenatal cannabis exposure increases the likelihood of ASD, regardless of the child’s sex or gestational age at birth. This research, titled “Examining the Association Between Prenatal Cannabis Exposure and Child Autism Traits: A Multi-cohort Investigation in the Environmental influences on Child Health Outcomes (ECHO) Program,” is published in Autism Research.

This study included children and their mothers from 34 ECHO cohorts across the United States. ECHO researchers gathered data on cannabis use during pregnancy directly from mothers and from their medical records. They also collected information on ASD diagnosis, as well as caregiver-reported data on the children’s autism traits when the children were 1 to 18 years. The researchers used these data and reports to test whether prenatal cannabis use might be associated with ASD.

“With the legalization of cannabis in some areas of the United States, there has been a decrease in the perception of risk and an increase in cannabis use among pregnant women,” said Chaela Nutor. “While fetal exposure to cannabis has been linked to poorer neonatal and cognitive outcomes, relatively few studies have tested the association between prenatal cannabis exposure and autism spectrum disorder.”

The results of this study supported the findings from previous studies showing that initial unadjusted associations between prenatal cannabis exposure and ASD behaviors in school-aged children are no longer significant when controlling for other factors, such as maternal use of other substances during pregnancy.

The researchers are planning another large national study to further investigate the relationship between prenatal cannabis exposure and autism-related behaviors. Future work could examine the role of continued exposure to cannabis after mothers are aware of pregnancy, and other studies could investigate combined exposure to tobacco and cannabis and associated risk for ASD.

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Weight Gain During Infancy in Children Born Preterm Associated with Higher Risk of Obesity, According to New ECHO Research

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Weight Gain During Infancy in Children Born Preterm Associated with Higher Risk of Obesity, According to New ECHO Research

Authors: Michael O’Shea, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Infants born preterm typically have a period of poor growth in their first few months. After this stretch, they typically exhibit “catch-up” growth defined by an increase in weight z-score—a measure to classify a child’s nutritional status—during childhood and adolescence.

Prior research suggested that a “trade-off” may be associated with catch-up growth, such that individuals with more rapid weight gain during infancy have better neurodevelopmental outcomes than individuals with less weight gain. However, rapid catch-up growth during infancy has also been associated with a higher risk of becoming overweight or obese.

This study can help inform evidence-based guidelines for managing infant nutrition and growth monitoring after infants born very preterm (prior to 32 weeks of gestation) are discharged from a neonatal intensive care unit (NICU), to support rates of growth less likely to contribute to childhood overweight and obesity.

What were the study results?

In comparison to infants with low weight gain after birth, infants with very high weight gain after NICU discharge, which was experienced by 13.6% of participants, had higher body mass index (BMI) scores and a higher risk of obesity at 12-48 months.

The study team found no evidence that very high weight gain after NICU discharge was associated with better neurodevelopmental outcomes at 12 to 48 months of age. However, infants with very low weight gain after NICU discharge had lower scores on cognitive and language assessments. No significant differences were found between girls and boys.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was this study's impact?

The study’s findings suggest possible benefits of close monitoring of post-NICU growth and healthier feeding practices to prevent obesity, which is associated with multiple adverse health outcomes. However, as single studies rarely provide sufficient evidence to change clinical practice, the authors note that the current study should not be the sole basis for such changes.

Who was involved?

This study involved 1,400 children born before 32 weeks of gestation in hospitals in multiple states in the U.S. between 2002 and 2020. A majority of these children experienced neonatal complications—issues faced during the first 28 days of life—the most common of which was neonatal chronic lung disease.

What happened during the study?

After birth, the participants were followed for 1 to 4 years, at which point their BMI and neurodevelopmental outcomes were assessed. Data about each of the participants were shared, with appropriate informed consent from a parent or guardian, with the ECHO Cohort Consortium. This allowed for analyses of relationships between weight gain following NICU discharge and neurodevelopmental outcomes and BMI at 1 to 4 years of age.

What happens next?

Future studies are needed to evaluate the relationship between the pace of weight gain during early childhood, long-term developmental outcomes, and changes in children’s BMI. This study focused on weight gain among infants born very preterm after discharge from the NICU. Additional studies are needed to observe the effects of different rates of catch-up growth on infants born closer to term.

Where can I learn more?

Access the full journal article, titled “Association of Growth During Infancy with Neurodevelopment and Obesity in Children Born Very Preterm: The Environmental influences on Child Health Outcomes Cohort,” in the Journal of Pediatrics.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August 2024

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Weight Gain During Infancy in Children Born Preterm Associated with Higher Risk of Obesity, According to New ECHO Research

COVID-19 Pandemic Altered Relationship Between Neighborhood Environment and Child Well-Being, ECHO Study Suggests

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COVID-19 Pandemic Altered Relationship Between Neighborhood Environment and Child Well-Being, ECHO Study Suggests

Authors: Xueying Zhang, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Understanding how neighborhood characteristics affect child well-being is important. Prior studies have found an association between neighborhood characteristics and children’s health and development. During the COVID-19 pandemic, stay-at-home policies limited people’s interactions with their neighborhood environment. However, researchers have not considered how the pandemic might have changed these effects. ECHO researchers wanted to address this gap by exploring how the pandemic, as a natural experiment, may have changed the relationship between neighborhood characteristics and child well-being. Additionally, since COVID-19 has impacted racial and ethnic groups differently, this study examined these differences to identify potential disparities.

What were the study results?

The study found that the relationship between neighborhood characteristics and child well-being changed during the COVID-19 pandemic. It also revealed racial disparities, showing that the pandemic's impact on child well-being varied across different racial and ethnic groups.

For non-Hispanic White children, the number of people who lived in their homes and the diversity of their neighborhood were linked to lower well-being. For children of other races and ethnicities, living in areas with higher percentages of Hispanic residents and more adults working as essential workers were associated with lower well-being.

What was the study's impact?

These findings highlight how neighborhood characteristics, the pandemic, and child well-being interact, emphasizing the importance of addressing disparities during unique events like the pandemic.

Who was involved?

The study involved 1,039 children, mostly between the ages of 11 and 19, from more than 10 ECHO Cohort Study Sites across the U.S.

What happened during the study?

Researchers conducted an analysis of children who completed a well-being questionnaire called the Patient-Reported Outcomes Measurement Information System (PROMIS) before (2019 to March 1, 2020) and during (March 1, 2020 to August 31, 2021) the pandemic. The PROMIS survey measures children's mental and physical health and peer and family relationships.

The researchers then matched U.S. Census tract data with a child’s residential address to examine the neighborhood characteristics. They looked at factors including the race, education, and occupation composition of residents, as well as house capacities and property features. They analyzed how these factors were associated with child well-being, considering the impacts of the pandemic, as well as differences across child racial groups.

Note: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Future research could explore how specific aspects of neighborhoods affect children's well-being, especially when these factors interact.

Where can I learn more?

Access the full journal article, titled “Associations between neighborhood characteristics and child well-being before and during the COVID-19 pandemic: A repeated cross-sectional study in the Environmental influences on Child Health Outcomes (ECHO) program,” in Environmental Research.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

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Published July 1, 2024

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COVID-19 Pandemic Altered Relationship Between Neighborhood Environment and Child Well-Being, ECHO Study Suggests

ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

Authors: Jiwon Oh, Julie B. Schweitzer, Deborah H. Bennett, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health, supported this research.

Why was this study needed?

Phthalates are widely used chemicals found in many everyday items such as food packaging, flooring, building materials, medicine coatings, medical supplies, cosmetics, and personal care products. When phthalates enter the body, they are metabolized and converted into various smaller molecules, known as metabolites.

Animal studies suggest that exposure to phthalates during early life may negatively affect the nervous system, but there has been limited investigation into potential associations between early childhood phthalate exposure and attention-deficit/hyperactivity disorder (ADHD) behaviors in later childhood and adolescence.

For this study, ECHO researchers wanted to investigate whether exposure to phthalates in children at ages 2-5 years was associated with ADHD symptoms when these children were ages 8-18 years.

Learn how to say phthalate.

What were the study results?

ECHO Cohort researchers evaluated the levels of several metabolites that result from phthalate exposure. They saw that in children ages 2-5 years, most of these molecules were not associated with ADHD behaviors in these children at ages 8-18 years.

However, among children who had been diagnosed with autism spectrum disorder (ASD), one of these metabolites—mono-2-heptyl phthalate (MHPP)—was associated with more ADHD behaviors. Among typically developing children, a different small molecule—mono-carboxy isooctyl phthalate (MCiOP)—was associated with more hyperactive/impulsive behaviors.

What was this study's impact?

This study suggests that early childhood exposure to certain phthalates may be associated with having both ASD and ADHD traits. Since ADHD behaviors are more commonly found in children with ASD, deepening the understanding of how exposure to environmental chemicals, such as phthalates, could contribute to this comorbidity may be important for managing and treating these conditions effectively.

Note: The results reported here are from a single study. Other or future studies may provide new information or different results. You should consult with a qualified healthcare provider for diagnosis and for answers to your personal questions.

Who was involved?

This study included 243 children living in Northern California and taking part in the ReCHARGE (Revisiting Childhood Autism Risks from Genetics and Environment) study. This study included both neurotypical and neurodiverse children, with about 60% of them having ever had neurodevelopmental concerns. Therefore, the children included in the study tended to have more ADHD behaviors compared with children in the general population.

What happened during the study?

Phthalate metabolites can be measured in biological samples, such as urine, to assess exposure to phthalates. In this study, the researchers measured 15 phthalate metabolites in urine samples of young children ages 2-5 years. Parents answered questions about each child’s ADHD symptoms at ages 8-18 years.

What happens next?

While the metabolite MHPP and the phthalate it’s derived from, di-n-heptyl phthalate (DHPP), are commonly found in children’s urine, their influence on neurodevelopment has not been studied as much as other phthalates. Since exposure to DHPP has been linked to problems with development and behavior in animals, further studies need to look more closely at this compound to understand its effects on how the brain develops in children.

Where can I learn more?

Read the full research article, titled “Early childhood exposures to phthalates in association with attention-deficit/hyperactivity disorder behaviors in middle childhood and adolescence in the ReCHARGE study,” in the journal International Journal of Hygiene and Environmental Health.

Learn more about ECHO’s other chemical exposure research.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published June 2024

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

No Significant Correlation Found Between Labor-inducing Drug During Childbirth and Future Risk of ADHD and Autism Spectrum Disorder in Children, Study Finds

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No Significant Correlation Found Between Labor-Inducing Drug During Childbirth and Future Risk of ADHD and Autism Spectrum Disorder in Children, Study Finds

Synthetic oxytocin was associated with lower ADHD risk among children born to mothers with pre-pregnancy obesity. Mothers with pre-pregnancy obesity were more inclined to receive labor-inducing medication.

Authors: Lisa Kurth, PhD, et al.

Who sponsored this study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) Program, Office of The Director, National Institutes of Health.

Why was this study needed?

More than 50% of U.S. childbirths are assisted with synthetic oxytocin (sOT)—known by trade names such as Pitocin or Syntocinon—a drug that promotes labor by stimulating the muscles in the uterus to contract. As rates of child ADHD and autism spectrum disorder (ASD) diagnoses are steadily rising, researchers have attempted to identify risk factors that might be contributing to these increases. There have been conflicting results from previous studies investigating the link between sOT exposure and childhood risk of ADHD and ASD. Additionally, the potential effect of the mother’s pre-pregnancy body mass index (BMI) on this association has not yet been studied.

What were the study results?

Analysis of data from a large and diverse ECHO Cohort sample suggests that maternal exposure to sOT during childbirth was not associated with an increased risk for ADHD or ASD in offspring. Associations did not differ by sex. Unexpectedly, sOT was associated with lower ADHD risk among children born to mothers with pre-pregnancy obesity.

The study also found that 48% of laboring mothers received sOT. Researchers saw slightly higher usage of sOT in mothers with pre-pregnancy obesity.

What was this study's impact?

The findings raise questions about how these drugs might affect health outcomes, especially when combined with maternal obesity during pregnancy. Additionally, the findings indicate that maternal obesity may influence the need for interventions during childbirth. These results do not currently support a need to modify the clinical use of sOT during childbirth.

What happened during the study?

A team of researchers used statistical analysis to examine the association between sOT exposure during labor and child ADHD or ASD diagnosis. Investigators also evaluated whether maternal pre-pregnancy BMI and child sex affected this correlation.

Note: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

Who was involved?

This study included over 12,000 mother-child pairs from 44 ECHO Cohort research sites across the U.S. Of the mothers participating in this study, 48% were exposed to sOT during childbirth.

What happens next?

More research is needed to evaluate if the dosage and duration of sOT has any influence on children's neurodevelopment. Future studies may clarify how environmental exposures and other contributing factors, such as delivery method and maternal obesity at delivery, influence a child’s neurodevelopment. Examining maternal/fetal biospecimens could also reveal how this exposure affects mothers and babies.

Where can I learn more?

Access the full journal article, titled “Intrapartum Exposure to Synthetic Oxytocin, Maternal BMI, and Neurodevelopmental Outcomes in Children within the ECHO Consortium” in the Journal of Neurodevelopmental Disorders.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published May 26, 2024

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No Significant Correlation Found Between Labor-Inducing Drug During Childbirth and Future Risk of ADHD and Autism Spectrum Disorder in Children, Study Finds

ECHO Cohort Research Investigates Relationship Between Infant Gut Microbiome and Childhood Autism-related Traits

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ECHO Cohort Research Investigates Relationship Between Infant Gut Microbiome and Childhood Autism-related Traits

Authors: Vanja Klepac-Ceraj, Juliette C. Madan, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

The relationship between a person’s gut bacteria and the brain during early childhood, especially from birth to around age three years, helps the immune and nervous systems develop and function. The gut microbiome could be a promising area of research to understand the development of autism-related traits. Previous studies have found links between gut bacteria and social traits, but the results are not the same in different populations. To include a broader population of children in the U.S., researchers in this study sought to identify gut bacteria linked to social traits and brain development in two ECHO Cohort Study Sites.

What were the study results?

Researchers found that certain features of the gut microbiome of infants were associated with higher scores on the Social Responsiveness Scale-2 (SRS-2), a questionnaire that measures autism-related traits. Specifically, certain bacteria and their functional genes, particularly those related to the production of short-chain fatty acids, were linked to autism-related traits. These associations varied between sex and age groups.

Note: Results reported here are for a single study. Other or future studies may provide new information or different results. You should always consult with a qualified healthcare provider for diagnosis and for answers to your personal questions.

What was this study's impact?

Understanding the potential likelihood of autism-related traits through the lens of the gut-brain axis opens new avenues for targeted interventions in early life.

Who was involved?

Researchers studied 481 samples from 304 healthy child participants from two ECHO Cohort study sites in New Hampshire and Rhode Island. The children were between 6 weeks old and 2 years old when they provided stool samples and between 3 and 19 years old when social traits were assessed.

What happened during the study?

The researchers compared groups of participants from two different study sites, focusing on their gut microbiomes when they were younger and social traits related to ASD at a later age. Both study sites contributing to this analysis had previously sequenced bacterial DNA from fecal samples collected from infants or toddlers. They calculated how common certain bacteria were in each sample and related that to the participant’s social behavior scores.

What happens next?

Future studies could explore interventions that could change the gut bacteria and potentially influence how the brain develops. Researchers also plan to investigate the influence of the developing gut microbiome on other neurobehaviorial outcomes, such as anxiety and depression.

Where can I learn more?

Access the full journal article, titled “Prospective Association of the Infant Gut Microbiome with Social Behaviors in the ECHO Consortium,” in Molecular Autism.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published May 17, 2024

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ECHO Cohort Research Investigates Relationship Between Infant Gut Microbiome and Childhood Autism-related Traits

ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

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ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

Authors: Himal Suthar, Max Aung, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Per- and polyfluoroalkyl substances (PFAS) are a large, complex group of synthetic chemicals that have been used in consumer products around the world since about the 1950s. They are ingredients in various everyday products. For example, PFAS are used to keep food from sticking to packaging or cookware, make clothes and carpets resistant to stains, and create firefighting foam that is more effective. People are most likely exposed to these chemicals by consuming PFAS-contaminated water or food, using products made with PFAS, or breathing air containing PFAS.

Because PFAS break down slowly, if at all, people and animals are repeatedly exposed to them, and blood levels of some PFAS can build up over time. Scientific studies have identified multiple health effects associated with PFAS exposure.[1] Women exposed to PFAS during pregnancy are at increased risk for adverse birth outcomes and pregnancy complications.

Lipids are fatty molecules that perform a variety of functions in the body—from forming the membranes of cells to serving as a building block for certain hormones. Changes in bioactive lipids—broadly defined as a category of lipids with signaling properties that cause biological effects and changes in the body—have been linked to PFAS exposure and adverse pregnancy outcomes. This study aimed to compare the concentration of PFAS in the blood of pregnant participants with levels of bioactive lipids in three important metabolic pathways.

[1] National Institute of Environmental Health Sciences: Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) (nih.gov)

What were the study results?

The research team analyzed the associations between 12 types of PFAS, in pairs and as mixtures, and 50 bioactive lipids in blood plasma in pregnant participants across three ECHO Cohort Study Sites. When researchers looked at data from different study sites, they found that higher levels of PFAS in blood were often linked with higher levels of certain bioactive lipids. The research team also noticed differences in the distribution of bioactive lipid compounds between individual study sites, possibly driven by variations in the genetic makeup and sociodemographic characteristics of the populations or differences in environmental exposures due to diet.

Footnote: Results reported here are for a single study and reflect an observed correlation. Other or future studies may provide new information or different results. You should always consult with a qualified healthcare provider for diagnosis and for answers to your personal questions.

What was this study's impact?

The similarity of results researchers found from the analysis of mixtures of PFAS chemicals and individual PFAS chemicals indicate that specific bioactive lipids could be useful biomarkers of PFAS exposure. Biomarkers are biological indicators of a particular health effect or status – in this case, PFAS exposure. They can be found in blood, urine, or other body fluids and can be substances, characteristics, genes, or proteins. This insight could help in understanding and addressing the health effects of PFAS by expanding screening methods.

The bioactive lipids measured in this study have not yet been tested as routine biomarkers in clinical settings. However, these findings aid in advancing the future of healthcare as additional and more complex lipid biomarkers become measurable and are tested for clinical use.

These findings encourage researchers to prioritize the study of PFAS and bioactive lipids pairs in future testing in addition to individually studying the effect of different types of PFAS. Additionally, this study highlights the importance of regulating the 12 types of PFAS observed.

Who was involved?

This study included 414 pregnant participants from three ECHO Cohort study sites: Chemicals in Our Bodies based in San Francisco, ECHO-PROTECT based in Puerto Rico, and Illinois Kids Development Study based in Chicago.

What happened during the study?

The research team estimated associations between prenatal PFAS exposure and bioactive lipids, measuring the levels of 12 types of PFAS and 50 bioactive lipids in 414 pregnant participants. Researchers quantified associations by using various statistical analyses while controlling for several factors (e.g., maternal age, gestational age at sample collection, maternal education, pre-pregnancy BMI).

What happens next?

The researchers plan to measure associations between bioactive lipids and peri- and prenatal mental health outcomes including perinatal and postpartum depression. Future studies could also look at the influence of other variables on this relationship. For example, researchers could investigate the influence of diet, which has been linked to changes in both PFAS and bioactive lipid concentrations.

Where can I learn more?

Access the full journal article, titled “Cross-Sectional Associations between Prenatal Per- and Poly-Fluoroalkyl Substances and Bioactive Lipids in Three Environmental Influences on Child Health Outcomes (ECHO) Cohorts,” in Environmental Science and Technology.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published May 14, 2024

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ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

ECHO Study Investigates Relationship Between Phthalate Exposure and High Blood Pressure, Related Complications During Pregnancy

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ECHO Study Investigates Relationship Between Phthalate Exposure and High Blood Pressure, Related Complications During Pregnancy

Authors: John Meeker, Jordan Kuiper, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

High blood pressure during pregnancy, which can develop into the more serious conditions of preeclampsia* or eclampsia*, can pose significant health risks to pregnant women and their children. Potential environmental risk factors for ongoing high blood pressure during pregnancy and more severe pregnancy complications like preeclampsia or eclampsia have not been well-studied. Phthalates are chemicals used in various products, including plastics, personal care products, and food packaging. There is evidence, though limited, that exposure to some phthalates may be associated with preeclampsia and ongoing high blood pressure during pregnancy.

*Preeclampsia and eclampsia are pregnancy-related high blood pressure disorders. In preeclampsia, the mother’s high blood pressure reduces the blood supply to the fetus, which may get less oxygen and fewer nutrients. Eclampsia is when pregnant women with preeclampsia develop seizures or coma.

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What were the study results?

The researchers evaluated phthalate exposure by measuring urine levels of certain metabolites, which are small molecules the body makes when it breaks down foods, drugs, chemicals, or its own tissues (for example, fat or muscle tissue). This study found that higher levels of these metabolites were associated with a higher risk of developing preeclampsia, eclampsia, and/or ongoing high blood pressure during pregnancy. For example, a doubling of mono (3-carboxypropyl) phthalate (MCPP)—a metabolite linked to phthalates found in PVC-based plastics and insect repellents—was associated with 12% increased risk of developing preeclampsia or eclampsia.

For combined exposures, researchers divided participants into four groups, or quartiles, by increasing level of exposure. A quartile increase in the combined phthalate mixture was associated with a 27% increased risk of preeclampsia or eclampsia. This effect was generally larger among pregnant participants carrying female fetuses.

What was this study's impact?

The findings of this study suggest that exposure to certain phthalates found in plastics and other consumer products may be associated with pregnancy complications like gestational hypertension or preeclampsia.

Who was involved?

The study included data from 3,430 participants from eight ECHO sites across the U.S. which enrolled pregnant participants from 1999 to 2019.

What happened during the study?

The researchers measured the levels of 13 metabolites linked to phthalate exposure in urine samples collected at least once during pregnancy. They then evaluated the association between individual phthalates, as well as the combined mixture of phthalates, with the risk of developing preeclampsia, eclampsia, or ongoing high blood pressure during pregnancy.

Note: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Additional well-designed studies are needed to better understand the association between phthalate exposure and high blood pressure during pregnancy, the underlying biological mechanisms, and effective interventions that could reduce the risk of these kinds of pregnancy complications.

Where can I learn more?

Access the full journal article, titled “Urinary concentrations of phthalate metabolites in relation to preeclampsia and other hypertensive disorders of pregnancy in the Environmental influences on Child Health Outcomes (ECHO) program,” in Environment International.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published May, 2024

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ECHO Study Investigates Relationship Between Phthalate Exposure and High Blood Pressure, Related Complications During Pregnancy