ECHO Study Investigates Relationship Between Chemical Exposures, Pregnancy Stress, & Birth Outcomes

Authors: Stephanie Eick, Anne Dunlop, 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?

Most previous research on the effects of chemical exposures on birth outcomes has focused on a small number of well-established chemicals, such as bisphenol A (BPA) and certain phthalates. However, there are over 350,000 chemicals registered for global use, and the impact of many emerging or understudied chemicals on birth outcomes is not well understood. Additionally, prior studies have not adequately considered how different kinds of maternal stress (such as anxiety, depression, and adverse childhood experiences) might influence the effects of chemical exposures during pregnancy. This study examined a broader range of chemicals and evaluated the role of stress in influencing their associations with birth outcomes.

What were the study results?

Exposure to chemicals found in certain consumer and industrial products (such as phthalates, bisphenols, and insecticides) was associated with shorter pregnancies among women who experienced anxiety during pregnancy or in the early postpartum period. Depression modified how exposure to certain chemicals (such as phthalates, parabens, and insecticides) affected birthweight and length of pregnancy. Some chemicals positively correlated with length of pregnancy (duration) for mothers with more depression, while others were associated with lower birthweights when mothers had more depression symptoms. The study suggested that the effects of a mother’s stress on the relationship between chemical exposures and birth outcomes depended on the type of chemical and type of stressor experienced.

What was this study's impact?

This study found that exposure to chemicals commonly found in consumer products was associated with shorter pregnancies and lower among women experiencing anxiety during or after pregnancy. While the results were mixed, the researchers observed some patterns where effects of chemical exposures were strongest among mothers who experienced depression and anxiety. These findings suggest that screening for depression and anxiety during pregnancy could help identify women who may be at a higher risk of adverse birth outcomes.

Who was involved?

The study included 1,556 mother-child pairs from 11 ECHO Cohort Study Sites. 810 of these participants provided information on perceived stress, depression, and anxiety. Additionally, participants provided information on adverse childhood experiences.

What happened during the study?

Pregnant participants provided urine samples, which researchers analyzed for 113 chemicals from 10 chemical classes. Pregnant participants also reported on their stress, depression, anxiety, and adverse childhood experiences. Researchers collected information on each mother’s birth outcomes, including the length of their pregnancy (in weeks) and the baby’s birthweight. The researchers performed statistical analyses to examine associations between chemical exposures, stress, and birth outcomes.

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?

Additional studies looking at the combined effects of multiple combined exposures could help researchers better understand the role of these factors in influencing birth outcomes. Future research could also further investigate potential biological effects of maternal adverse childhood experiences.

Where can I learn more?

Access the full journal article, titled “Psychosocial Stressors as Modifiers of the Associations Between Well-Studied and Understudied Chemicals and Birth Outcomes in the ECHO Cohort,” in Environmental Pollution.

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

Published January 15, 2026

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ECHO Study Investigates Relationship Between Chemical Exposures, Pregnancy Stress, & Birth Outcomes

Pregnancy Stress Can Influence Relationship Between Chemical Exposures & Birth Outcomes, ECHO Study Finds

Posted on January 7, 2026January 7, 2026 by Jodi Snare

Stress, anxiety, and depression during pregnancy and maternal adverse childhood experiences may influence the relationship between certain chemical exposures and birth outcomes, according to a new ECHO Cohort study led by Stephanie Eick, PhD, MPH and Anne Dunlop, MD, MPH of Emory University.

Most previous research on the effects of chemical exposures on birth outcomes has focused on a small number of well-established chemicals, such as bisphenol A (BPA) and certain phthalates. However, there are over 350,000 chemicals registered for global use, and the impact of many emerging or understudied chemicals on birth outcomes is not well understood. Additionally, prior studies have not adequately considered how different kinds of maternal stress (such as anxiety, depression, and adverse childhood experiences) might influence the effects of chemical exposures during pregnancy.

This study included 1,556 mother-child pairs from eleven ECHO Cohort Study Sites across the United States. Researchers analyzed urine samples from pregnant participants for 113 different chemicals from 10 chemical classes. Participants also reported on their stress, depression, anxiety, and adverse childhood experiences, allowing researchers to evaluate how these factors affect the relationship between different chemical exposures and birth outcomes.

Key Takeaways include:

Exposure to chemicals found in certain consumer and industrial products (such as phthalates, bisphenols, and insecticides) was associated with shorter pregnancies among women who experienced anxiety during pregnancy or in the early postpartum period.
Depression modified how exposure to certain chemicals (such as phthalates, parabens, and insecticides) affected birthweight and length of pregnancy.
Some chemicals positively correlated with length of pregnancy (duration) for mothers with more depression, while others were associated with lower birthweights when mothers had more depression symptoms.
The effects of a mother’s stress on the relationship between chemical exposures and birth outcomes depended on the type of chemical and type of stressor experienced.

“These findings suggest that screening for depression and anxiety during pregnancy could help identify women who may be at a higher risk of adverse birth outcomes,” said Dr. Eick.

Additional studies looking at the combined effects of multiple combined exposures could help researchers better understand the role of these factors in influencing birth outcomes. Future research could also further investigate potential biological effects of maternal adverse childhood experiences.

This collaborative research, titled “Psychosocial Stressors as Modifiers of the Associations Between Well-Studied and Understudied Chemicals and Birth Outcomes in the ECHO Cohort,” is published in Environmental Pollution.

Read the research summary.

NIH Study Highlights Potential Disparities in Birthweight Outcomes Linked to Environmental Exposures in Vulnerable Populations

Posted on December 4, 2024April 2, 2025 by Jodi Snare

A new study from the Environmental influences on Child Health Outcomes (ECHO) Program sheds light on how environmental exposures may have a larger impact on birth outcomes in vulnerable populations, particularly those defined by race, ethnicity, and maternal education. Researchers wanted to understand when the effect of these exposures becomes clinically significant and how different levels of exposure impact various groups differently.

To explore this, researchers used statistical models to simulate four potential scenarios in which average birthweights in a population could be reduced by varying amounts: 50g, 125g, 167g, and 250g. The study found that the percentage of children with low birthweight (LBW) (birthweight<2500g) varied by socioeconomic categories with the greatest percentage LBW seen in the most vulnerable socioeconomic groups. After analyzing the four scenarios, a clear trend was seen such that the greatest impact of an exposure was seen in the most vulnerable sub-populations. This trend was observed for all scenarios including the impact of a small environmental exposure. The most striking disparity among all scenarios was found in racial sub-populations.

This study showed how vulnerable groups, who already face higher risks of poor health, are more affected by small environmental exposures compared to the general population. Read a research summary here.

Nutrition That Aligns With Guidelines During Pregnancy May Be Associated With Better Infant Growth Outcomes, NIH Study Finds

Posted on November 22, 2024August 27, 2025 by Jodi Snare

Expectant mothers who maintain a diet that meets USDA dietary guidelines during pregnancy may be more likely to have infants with healthy birthweights, steadier growth patterns, and potentially a reduced risk of obesity later in childhood, according to a new study funded by the Environmental influences on Child Health Outcomes (ECHO) Program at the National Institutes of Health.

The research, involving more than 2,800 mother-child pairs across eight ECHO Cohort Study Sites, suggests that following a healthy prenatal diet in line with the USDA Dietary Guidelines for Americans could have long-term positive effects on infant growth up to 24 months.

“This study found that eating a healthy diet during pregnancy was linked with a lower chance of extremely rapid infant growth,” said Assiamira Ferrara, MD, PhD, of Kaiser Permanente Northern California Division of Research. Dr. Ferrara noted that rapid growth from birth to 24 months is a strong predictor of obesity later in life.

The study used two dietary measures—the Healthy Eating Index (HEI) and the Empirical Dietary Inflammatory Pattern (EDIP)—to look at maternal eating patterns. The HEI measures overall diet quality. The EDIP score measures how likely a diet is to cause inflammation in the body. Diets with high EDIP scores have been linked to increased levels of inflammation.

Key findings from the research showed that:

Higher HEI scores, reflecting healthier diets, were associated with a 12% reduced chance of infants being born large for gestational age (LGA), alongside lower rates of rapid growth up to 6 and 24 months.
Lower EDIP scores, indicating diets with reduced inflammatory potential, were associated with a 24% higher chance of LGA and had mixed effects on growth: slower from birth to 6 months but faster growth between birth and 12 months. This association was less clear and warrants further study.

To assess rapid growth, the study relied on a measurement called the weight-for-length z-score (WLZ) a tool used to track an infant's growth. It compares a baby’s weight to its length and tells you how far a baby's weight is from the average weight of babies of the same length. Rapid growth was defined as a significant increase in WLZ scores from birth to 6, 12, or 24 months. Babies whose WLZ scores jumped more than expected moved to a higher percentile on the growth chart, meaning they weighed more relative to their peers of the same length.

“The findings support a role for a balanced prenatal diet that aligns with the USDA Dietary Guidelines in promoting healthy birthweights and balanced growth through early childhood,” said Monique Hedderson, PhD, of Kaiser Permanente Northern California Division of Research. “This suggests the need for programs to help improve pregnant womens' access to healthy food and interventions to support healthy eating during pregnancy.”

Researchers said that the findings represent an opportunity for an early obesity prevention strategy. More research is needed to learn how low-inflammatory diets during pregnancy might benefit fetal and infant growth.

About the Study

The study analyzed data collected between 2007 and 2021 from the ECHO Program about 2,854 mother-child pairs. Among the children studied, 48.7% were girls. Children came from diverse racial and ethnic backgrounds: 23.3% White, 22.4% Black, 35.8% Hispanic, 7.8% Asian, and 7.8% other racial backgrounds. Researchers collected information on diet, birth size, and infant growth at 6, 12, and 24 months through medical records and other measurement tools.

This collaborative research was published in JAMA Network Open.

Ferrara, A. & Hedderson, M. (2024) Prenatal Diet and Infant Growth from Birth to Age 24 months. JAMA Network Open. DOI:: 10.1001/jamanetworkopen.2024.45771

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About ECHO: Launched in 2016, the Environmental influences on Child Health Outcomes (ECHO) Program is a research program in the Office of the Director at the NIH with the mission to enhance the health of children for generations to come. ECHO investigators study the effects of a broad range of early environmental influences on child health and development. For more information, visit echochildren.org.

About the NIH: NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information, visit www.nih.gov.

Media Contacts

For information or to request an interview, contact Rebekah Yeager, rebekah.yeager@nih.gov.

If you are not a member of the media, but have a general inquiry, please contact NIHKidsandEnvironment@od.nih.gov.

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Check out the recent issues of our bi-monthly newsletter, the ECHO Connector, for program news and the latest research findings.

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Follow @ECHOChildHealth for the latest ECHO Program updates on X.

ECHO Study Investigates Nutrition During Pregnancy and Infant Growth Outcomes

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ECHO Study Investigates Nutrition During Pregnancy and Infant Growth Outcomes

Authors: Monique Hedderson, Assiamira Ferrara, 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?

Nearly one-third of children in the U.S. have overweight or obesity, putting them at risk of adverse health outcomes later in life. More research is needed to inform prevention strategies during critical periods of growth, including pregnancy. This study aimed to understand the association between diet quality during pregnancy and infant growth. Rapid growth from birth to 24 months has been identified as a strong predictor of obesity later in life. ECHO researchers looked at how a mother’s nutrition during this crucial period of development might influence the baby’s size at birth and their growth over time.

What were the study results?

Researchers used two indexes to measure healthy eating patterns: the Healthy Eating Index (HEI) and the Empirical Dietary Inflammatory Pattern (EDIP). These scales measure how well foods in a person’s diet align with the U.S. Dietary Guidelines and the diet’s inflammatory potential, respectively. Expectant mothers with higher HEI scores were more likely to have babies with a healthy birthweight and fewer growth issues. Specifically, higher HEI scores were associated with a 12% lower chance of having a baby born large for gestational age (LGA) and a lower chance of rapid growth from birth to 6 months and birth to 24 months. By contrast, a lower score on the EDIP, indicating a less inflammatory diet, was associated with a 24% higher chance of LGA and slower growth to 6 months but faster growth from birth to 12 months. This association was less clear and warrants further study.

What was this study's impact?

The study's findings support the idea that a prenatal diet aligning with U.S. Dietary Guidelines, measured by the HEI, may promote healthy birthweight and infant growth through 24 months. The findings suggest that following USDA dietary guidelines during pregnancy may improve long-term infant growth. This highlights the need for programs or interventions to help pregnant individuals adopt healthy diets.

Who was involved?

The study included 2,854 mother-child pairs from eight ECHO Cohort Study Sites. Among the children, 48.7% were girls, 23.3% were White, 22.4% were Black, 35.8% were Hispanic, 7.8% were Asian, and 7.8% came from other racial backgrounds.

What happened during the study?

The study examined data from mothers and their children in eight different groups that were part of the ECHO Program between 2007 and 2021. Researchers used medical records and study weight and height measurements to track the babies' sizes and growth over time. The mothers' diets during pregnancy were evaluated to calculate HEI and EDIP scores. The study then explored how these diet patterns were associated with babies' size at birth and their growth up to 6, 12, and 24 months old.

To assess rapid growth, the study relied on a measurement called the weight-for-length z-score (WLZ) a tool used to track an infant's growth, it compares a baby’s weight to their length, and tells you how far a baby's weight is from the average weight of babies of the same length. Rapid growth was defined as a significant increase in WLZ scores from birth to 6, 12, or 24 months. Babies whose WLZ scores jumped more than expected moved to a higher percentile on the growth chart, meaning they weighed more relative to their peers of the same length.

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?

More research is needed to understand the potential benefits of low-inflammatory prenatal dietary patterns in fetal and infant growth. Future studies could investigate how an infant's appetite and feeding habits might influence the connection between a mother's diet during pregnancy and the baby's long-term growth.

Where can I learn more?

Access the full journal article, titled “Prenatal Diet and Infant Growth from Birth to Age 24 months,” in JAMA Network Open.

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

Published November 21, 2024

Read the associated press release.

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ECHO Study Investigates Nutrition During Pregnancy and Infant Growth Outcomes

Vulnerable Populations More Likely to be Impacted by Small Environmental Effects, ECHO Study Finds

Authors: Janet L. Peacock, 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?

A challenge in public health is determining when the effect of an environmental exposure is large enough to be clinically important. Vulnerable populations—defined by sociodemographic factors such as race, ethnicity, and maternal education—tend to have a higher risk of poor health outcomes than the general population when exposed to the same environmental exposures. This study aimed to interpret the differences in outcomes between different population types, particularly focusing on vulnerable sub-populations, by analyzing differences arising from hypothetical small effects on these groups.

What were the study results?

The researchers used statistical models to examine how different levels of exposures would affect different sub-populations within the nationwide ECHO Cohort. Specifically, the study team considered a hypothetical environmental exposure that could affect a child’s birthweight. They considered four scenarios in which the hypothetical exposure could affect average birthweights in a population: a very small effect reducing average birthweight by 50g, a small effect reducing it by 125g, a medium effect reducing it by 167g, and a large effect reducing it by 250g.

The study found that the percentage of children with low birthweight (LBW) (birthweight<2500g) varied by socioeconomic categories with the greatest percentage LBW seen in the most vulnerable socioeconomic groups. After analyzing the four scenarios, a clear trend was seen such that the greatest impact of an exposure was seen in the most vulnerable sub-populations. This trend was observed for all scenarios including the impact of a small environmental exposure.

What was this study's impact?

This study showed how vulnerable groups, who already face higher risks of poor health, may be more affected by small environmental exposures than the general population. This demonstrates why small effects, which may be overlooked, are actually important when considering vulnerable populations. These results can be used in planning future studies and for designing preventive programs. The findings also help explain how exposures impact vulnerable groups and highlight the need to stratify by socioeconomic variables when assessing health outcomes.

Who was involved?

This simulation study modeled data from more than 28,000 mother-child pairs from the ECHO Cohort.

What happened during the study?

The research team conducted a simulation using data from ECHO Cohort participants to explore how hypothetical exposures could affect babies’ average birthweight and LBW in vulnerable subgroups. The study calculated average birthweight in groups by sociodemographic categories, and then compared the differences in average birthweight and the percentage of LBW.

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?

These findings are relevant for studies where researchers aim to identify the adverse effects of environmental exposures. Future research that uses more social factors and/or outcomes is needed to understand the impact of small environmental exposures on the general population and vulnerable sub-populations, and how these effects contribute to health disparities.

Where can I learn more?

Access the full journal article, titled “Do Small Effects Matter More in Vulnerable Populations? An Investigation Using Environmental influences on Child Health Outcomes (ECHO) Cohorts,” in BMC Public Health.

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

Published September 28, 2024

Read the associated research alert.

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Vulnerable Populations More Likely to be Impacted by Small Environmental Effects, ECHO Study Finds

Food Insecurity in Early Life, Pregnancy May Be Linked to Higher Chance of Obesity in Children, NIH-Funded Study Finds

Posted on September 16, 2024August 27, 2025 by Jodi Snare

FOR IMMEDIATE RELEASE

Family in grocery store

The study explores the effects of low-income, low-food-access neighborhoods on children’s obesity over time.

Children who faced food insecurity during early childhood—or whose mothers experienced it during pregnancy—had a higher body mass index (BMI) and more than 50% increased chance of developing obesity or severe obesity in childhood and adolescence, according to a new study funded by the NIH Environmental influences on Child Health Outcomes (ECHO) Program.

While previous research has linked food insecurity to obesity in adults, its impact on children is less clear. ECHO Cohort researchers explored how food insecurity during early life and pregnancy may affect the incidence of obesity in childhood and adolescence.

“Living in neighborhoods with access to healthy foods during these stages may be an important factor in preventing the development of obesity later in childhood and adolescence,” said Izzuddin M. Aris, PhD of the Harvard Pilgrim Health Care Institute. “Our findings support the need for further research on strategies to improve access to healthy food in early life.”

The study looked at data from nearly 30,000 mother-child pairs from 55 ECHO Cohort research sites nationwide. About 23% had mothers who lived in an area with limited access to grocery stores during pregnancy, and around 24% of the children lived in these areas during early childhood. Low-income-low-food-access (LILA) refers to a neighborhood with a third or more residents living more than one-half mile from a grocery store in urban areas or more than 10 miles in rural areas.

Key findings include:

Living in LILA neighborhoods during pregnancy or early childhood was associated with a higher BMI in the child at ages 5 and 15 and a more than 50% higher chance of developing obesity or severe obesity at ages 5, 10, and 15.
The associations became stronger as the children aged and were strongest among those who lived in LILA neighborhoods during early childhood and their mother’s pregnancy.

Researchers used participants' residential addresses from either pregnancy (1994 to 2023) or early childhood (1999 to 2023). They then matched these addresses with food access data from the USDA Food Access Research Atlas, which provides information on household income, vehicle availability, and neighborhood food access.

Data on children's weight and height were collected from birth through adolescence through in-person visits, medical records, and parent or caregiver reports. Researchers analyzed this data alongside the neighborhood information to investigate the relationship between food access and child BMI or obesity.

This collaborative research is published in JAMA Pediatrics.

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Aris, I.M., “Neighborhood Food Access in Early Life and Trajectories of Child Body Mass Index and Obesity in ECHO.” JAMA Pediatrics. DOI: 10.1001/jamapediatrics.2024.3459.

About ECHO: Launched in 2016, the Environmental influences on Child Health Outcomes (ECHO) Program is a research program in the Office of the Director at the NIH with the mission to enhance the health of children for generations to come. ECHO investigators study the effects of a broad range of early environmental influences on child health and development. For more information, visit echochildren.org.

About the NIH: NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information, visit www.nih.gov.

Media Contacts

For information or to request an interview, contact Rebekah Yeager, rebekah.yeager@nih.gov.

If you are not a member of the media, but have a general inquiry, please contact NIHKidsandEnvironment@od.nih.gov.

Connect With Us

Check out the recent issues of our bi-monthly newsletter, the ECHO Connector, for program news and the latest research findings.

To receive the ECHO Connector through email, subscribe here.

Follow @ECHOChildHealth for the latest ECHO Program updates on X (formerly known as Twitter).

Neighborhood-Level Poverty and Food Insecurity During Pregnancy Associated With Lower Birthweight and Small for Gestational Age Infants, NIH Study Finds

Posted on March 22, 2024August 27, 2025 by Jodi Snare

FOR IMMEDIATE RELEASE

Living in neighborhoods where residents have lower incomes and limited food access during pregnancy was associated with an increased risk of babies born small for gestational age or with lower birthweight, according to a new study from the NIH Environmental Influences on Child Health Outcomes (ECHO) Program.

Previous studies have shown that maternal diet during pregnancy can impact the physical and mental health of a mother. However, less is known about how food insecurity affects health outcomes for newborns. In a new research article, ECHO researchers analyzed data to understand what connections might exist between where a pregnant woman lives, their access to food, and birth outcomes.

This ECHO analysis, recently published in the American Journal of Clinical Nutrition, indicates a possible connection.

“Given the long-term effects of adverse birth outcomes on later cardiovascular disease risk and other conditions, more research is needed to evaluate whether interventions and policies that improve food access during pregnancy would be effective in improving birth outcomes and promoting child health,” said Izzuddin M. Aris, PhD, of the Harvard Pilgrim Health Care Institute.

Using nationwide data from more than 22,000 ECHO Cohort participants, a team of ECHO researchers found that, during pregnancy, 24% of those participants lived in a low-income neighborhood where a third or more residents lived over one mile from a grocery store (or more than 10 miles in rural areas). They also found that about 14% of the participants lived in neighborhoods with high poverty rates and where more than 100 households had no access to a vehicle and lived more than half a mile from the nearest grocery store.

Residence in low-income, low-food-access and low-income, low-vehicle-access neighborhoods was associated with lower birth weight, higher odds of babies born small for gestational age, and lower odds of babies born large for gestational age. However, researchers did not find any associations of individual food insecurity with birth outcomes.

To conduct this study, researchers matched pregnant individuals' home addresses with information about nearby food availability from the U.S. Food Access Research Atlas, which provided data on household income, the availability of a household vehicle, and where people can access food in different neighborhoods.

“In future studies, we want to look at health habits and chemical exposures to understand what else could be affecting birth outcomes,” said Dr. Aris.

Dr. Aris led a team of ECHO Cohort researchers from across the country who collaborated on the data analysis and writing for this research article.

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About ECHO: Launched in 2016, the Environmental influences on Child Health Outcomes (ECHO) Program is a research program in the Office of the Director at the NIH with the mission to enhance the health of children for generations to come. ECHO investigators study the effects of a broad range of early environmental influences on child health and development. For more information, visit echochildren.org.

About the NIH: NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information, visit www.nih.gov.

Read the research summary.

Media Contacts

For information or to request an interview, contact Rebekah Yeager, rebekah.yeager@nih.gov.

If you are not a member of the media, but have a general inquiry, please contact NIHKidsandEnvironment@od.nih.gov.

Connect With Us

Check out the recent issues of our bi-monthly newsletter, the ECHO Connector, for program news and the latest research findings.

To receive the ECHO Connector through email, subscribe here.

Follow @ECHOChildHealth for the latest ECHO Program updates on X (formerly known as Twitter).

ECHO Study Evaluates Influence of Neighborhood-Level Poverty and Food Insecurity During Pregnancy on Birthweight

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ECHO Study Evaluates Influence of Neighborhood-Level Poverty and Food Insecurity During Pregnancy on Birthweight

Authors: Izzuddin Aris, Emily Oken, 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?

Previous studies have shown that diet during pregnancy can impact the physical and mental health of the pregnant women. However, less is known about how food insecurity affects health outcomes for newborns. For this study, ECHO researchers analyzed data to understand what connections might exist between where a pregnant woman lives, their access to food, and birth outcomes.

What were the study results?

The study found that living in neighborhoods where residents have lower incomes, limited food access, or limited vehicle access was associated with lower birthweights and an increased risk of babies born small for gestational age. However, researchers didn’t find any association between individual experiences of food insecurity and birth outcomes.

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?

Given the long-term effects of adverse birth outcomes on later cardiovascular disease risk and other conditions, more research is needed to evaluate whether interventions and policies that improve food access during pregnancy would be effective in improving birth outcomes and promoting child health. A variety of strategies could be effective at improving birth outcomes, including strategies to increase neighborhood food access, improve food affordability in neighborhoods with low food access, or directly provide healthy foods to individuals during pregnancy.

Who was involved?

This study included 22,206 pregnant participants enrolled in 53 ECHO research sites that collected information on neighborhood-level food access data and birth outcomes. Of these participants, 24% lived in a low-income neighborhood where a third or more residents lived over one mile from a grocery store (or more than 10 miles in rural areas). About 14% of the participants in this study lived in neighborhoods with high poverty rates where more than 100 households had no access to a vehicle and lived more than half a mile from the nearest grocery store.

What happened during the study?

To conduct this study, researchers matched pregnant individuals' home addresses with information about nearby food availability from the U.S. Food Access Research Atlas, which provided data on household income, the availability of a household vehicle, and where people can access food in different neighborhoods. Researchers also assessed individual-level food insecurity during pregnancy using the Crisis in Family Systems-Revised questionnaire.

What happens next?

Additional studies are needed to examine how health habits, chemical exposures, and other related factors may also influence birth outcomes.

Where can I learn more?

Access the full journal article, titled “Birth Outcomes in Relation to Neighborhood Food Access and Individual Food Insecurity During Pregnancy in the Environmental influences on Child Health Outcomes (ECHO)-Wide Cohort Study,” in American Journal of Clinical Nutrition.

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

Published March 1, 2024

Read the associated article.

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ECHO Study Evaluates Influence of Neighborhood-Level Poverty and Food Insecurity During Pregnancy on Birthweight

ECHO Study Finds Flame-Retardant Chemicals May Increase Risk Of Preterm Birth and Higher Birth Weight

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ECHO Study Finds Flame-Retardant Chemicals May Increase Risk Of Preterm Birth and Higher Birth Weight

Authors: Deborah Bennett, Jiwon Oh, 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?

Manufacturers commonly use flame-retardant chemicals known as organophosphate esters (OPEs) in products such as furniture, baby items, electronics, clothes, and building materials to prevent fires and make plastics more flexible. People can come into contact with OPEs in various ways, including swallowing or breathing indoor dust or absorbing it through the skin. Animal studies have revealed that OPEs can harm the growth and development of offspring. However, the connection between OPE exposure during pregnancy and birth outcomes has been unclear. ECHO researchers wanted to learn if there was a link between OPE levels in the urine of pregnant individuals and specific birth outcomes.

What were the study results?

Pregnant individuals exposed to specific classes of OPEs may face an increased risk of preterm birth, especially for baby girls and babies with higher birth weights. Three of these substances—diphenyl phosphate (DPHP), a combination of dibutyl phosphate and di-isobutyl phosphate (DBUP/DIBP), and bis(1,3-dichloro-2-propyl) phosphate—were associated with shorter pregnancies and higher risks of preterm birth only among female infants. Among male infants, higher concentrations of DPHP were associated with longer pregnancies.

Babies born to mothers with detectable levels of three other OPE markers—bis(1-chloro-2-propyl) phosphate, bis(2-methylphenyl) phosphate, and dipropyl phosphate—tended to have higher birth weights compared to those whose mothers had no detectable levels of these substances.

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?

In the past decade, OPEs have been increasingly used as flame retardants after polybrominated diphenyl ether (PBDE) flame retardants were phased out due to health risks. ECHO research examines the potential impact of these now more widespread OPE chemicals on pregnancy outcomes such as preterm birth and birth weight. The findings can inform policies, programs, and practices to help decrease exposure.

Who was involved?

The study included 6,646 pregnant participants at 16 ECHO Cohort Study Sites across the U.S. and Puerto Rico.

What happened during the study?

Researchers measured a total of nine OPE markers in urine samples collected from 6,646 pregnant participants across 16 ECHO Cohort Study Sites—often during their third or second trimesters. The researchers then assessed birth outcomes, including the length of pregnancy and birth weight, using medical records or parent reports.

What happens next?

OPEs tend to stay in the human body for short periods, usually hours to days. To better understand how these chemicals might affect birth outcomes, researchers can use multiple measurements of urinary OPE biomarkers. This could help identify when the body might be more sensitive to these chemicals. Additionally, learning more about how people are exposed to these chemicals can help identify ways to reduce exposure, especially during pregnancy.

Where can I learn more?

Access the full journal article, titled “Associations of Organophosphate Ester Flame Retardant Exposures during Pregnancy with Gestational Duration and Fetal Growth: The Environmental influences on Child Health Outcomes (ECHO) Program,” in Environmental Health Perspectives.

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

Published January 24, 2024

Access the associated article.

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ECHO Study Finds Flame-Retardant Chemicals May Increase Risk Of Preterm Birth and Higher Birth Weight