Adverse Birth Outcomes May be Associated with Arsenic Levels in Public Drinking Water

Authors: Anne Nigra, 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?

Regulated U.S. public drinking water is a source of exposure to arsenic. Because arsenic occurs naturally, water that comes in contact with certain rocks and soils may contain it. Contamination from various industrial processes also contributes to increased levels of arsenic in some areas. Prenatal exposure to arsenic has been associated with adverse birth outcomes, including preterm birth and low birthweight. Researchers studied how arsenic in public drinking water—at levels below the federal limit—may affect birth outcomes in the ECHO Cohort. Previous evidence has been limited to private well exposures, studies using urinary biomarkers, and single-site studies with limited racial, ethnic, and geographic diversity.

What were the study results?

The study found that when pregnant women lived in areas with publicly reported high levels of arsenic in public drinking water, even at levels below the current federal safety standard of 10 micrograms per liter, their babies were more likely to be born with low birthweight (weighing less than 5 lbs 8 oz) or are small for their gestational age (smaller than babies born at the same number of weeks of pregnancy). These patterns were seen across several racial and ethnic groups, including White, Black, and Hispanic/Latino families. For example, babies born to Hispanic/Latino parents were about 40% more likely to have low birthweight with just a 5 microgram-per-liter increase in water arsenic. The study also found that babies born to Black parents had higher risks of being born early, with low birthweight, or smaller for their gestational age. Similar risks were observed among babies born to American Indian, Alaskan Native, Native Hawaiian, and Pacific Islander parents.

What was this study's impact?

The study shows that even low levels of arsenic in public drinking water may increase the risk of babies being born too early, too small, or underweight.

Who was involved?

Participants included 13,998 birthing mother-infant pairs from the ECHO Cohort.

What happened during the study?

Researchers estimated how much arsenic people were exposed to through public drinking water during pregnancy by combining water quality data with where each person lived each month. They then looked at whether that exposure was linked to outcomes like being born early (preterm birth), having a low birthweight, or being small for their gestational age.

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 research could help researchers understand how current efforts to reduce arsenic in drinking water are working—whether those efforts happen across the country, in local communities, in homes, or for individuals. Studies could also help identify where arsenic levels are highest, which may support ongoing work to make sure communities have safe drinking water.

Where can I learn more?

Access the full journal article, titled “Public water arsenic and birth outcomes in the Environmental influences on Child Health Outcomes Cohort,” 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 June 16, 2025

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Adverse Birth Outcomes May be Associated with Arsenic Levels in Public Drinking Water

A Diet High in Refined Grains and Low in Whole Grains in Pregnancy Linked to Lower Birthweights and Pre-term Births

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A Diet High in Refined Grains and Low in Whole Grains in Pregnancy Linked to Lower Birthweights and Pre-term Births

Analyzing Diets Based on Racial and Ethnic Groups May Better Predict Outcomes

Authors: Luis E. Maldonado, 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?

Researchers wanted to understand how a pregnant person’s diet, especially in relation to their blood sugar levels (fasting blood glucose), affects birth outcomes—like the baby’s weight and whether the baby is born early. Higher fasting blood glucose during pregnancy is known to increase the risk of adverse birth outcomes. However, little is known about whether culturally influenced combinations of foods and beverages play a meaningful role across different racial and ethnic groups. This question is important because, in the U.S., Hispanic pregnant women are disproportionately affected by adverse birth outcomes, such as preterm birth and low birthweight (under 5.5 pounds). By examining dietary patterns within racial and ethnic groups, the researchers aimed to uncover more precise links between diet and birth outcomes. These links might be overlooked when analyzing the population as a whole, since average diets often reflect the eating patterns of the most represented groups in the study.

What were the study results?

Refined grains, such as white bread or white rice, showed the strongest association with higher fasting blood sugar levels among Hispanic and non-Hispanic White women. People who ate diets high in refined grains and low in whole grains were more likely to have babies born with low birthweight, smaller for gestational age, or born preterm.

When dietary patterns were analyzed by racial and ethnic group, the associations between diet, blood sugar, and birth outcomes were stronger than when using a single pattern for the full population. In the group that included non-Hispanic White and Hispanic participants, nuts, seeds, and solid fats such as butter and lard were linked to lower blood sugar. Among non-Hispanic White participants, whole grains and solid fats had the strongest association with improved blood sugar control. In contrast, among Hispanic participants, higher fruit consumption was associated with elevated blood sugar levels. These food-specific associations should be considered within the overall dietary pattern, as individual foods can influence blood sugar – beneficially or adversely – within the broader diet.

What was the study's impact?

The results of this study show the importance of looking at dietary patterns within racial and ethnic groups, particularly in studies with varying representation of different racial and ethnic populations. Analyzing a single, combined group may mask group-specific associations between diet and birth outcomes, as the effects of diet can differ across racial and ethnic backgrounds.

Who was involved?

The study included 420 Hispanic and 564 non-Hispanic White pregnant participants from two ECHO Cohort study sites.

What happened during the study?

During the study, participants shared details about what they ate over a 24-hour period. The researchers analyzed the diets, along with the mother’s blood sugar, to help determine which combinations of foods eaten together in an overall diet are most closely linked to changes in blood sugar levels. They then tested whether the links between diet and birth outcomes were different across racial and ethnic groups by comparing findings from diets derived using group-specific versus combined fasting blood glucose, which have also been previously shown to vary by racial and ethnic population.

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 research could continue exploring how dietary patterns affect birth outcomes in diverse populations, especially by identifying patterns that are specific to different racial and ethnic groups.

Where can I learn more?

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

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

Published June 12, 2025

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A Diet High in Refined Grains and Low in Whole Grains in Pregnancy Linked to Lower Birthweights and Pre-term Births

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Pregnancy and birth

Obesity, Diabetes, & High Blood Pressure Before and During Pregnancy are Associated with Higher Blood Pressure in Children

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Obesity, Diabetes, & High Blood Pressure Before and During Pregnancy are Associated with Higher Blood Pressure in Children

Authors: Zhongzheng Niu, 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 in childhood is linked to a higher risk of experiencing high blood pressure and other heart-related complications later in life. Preventing high blood pressure during childhood could be a promising strategy to improve cardiovascular health into adulthood. Growing evidence suggests that maternal health during pregnancy may be a contributor. For this study, researchers wanted to look at how three common cardiometabolic risk factors— pre-pregnancy obesity, gestational diabetes, and high blood pressure (hypertension) during pregnancy—are related to blood pressure in their children between ages 2 and 18.

What were the study results?

A new finding from this study is that when mothers had more than one health issue during pregnancy—especially when high blood pressure occurred alongside gestational diabetes or pre-pregnancy obesity—their children’s blood pressure was higher than when the mother had only one of these conditions. Of the mothers included in this study, 44% had at least one cardiometabolic risk factor during pregnancy. The most common was pre-pregnancy obesity at 26%, followed by high blood pressure at 14% and gestational diabetes at 7.3%. Children whose mothers had any of these health issues during pregnancy had higher average blood pressure when compared to those born to mothers who did not. This was true for the top (systolic) and the bottom (diastolic) numbers in a blood pressure reading, even after accounting for the child’s age, sex, and height. These children also showed an increased rate of blood pressure change between ages 2 and 18. The association was stronger for diastolic blood pressure in female children and for systolic blood pressure in non-Hispanic Black children whose mothers had gestational diabetes or high blood pressure during pregnancy.

What was this study's impact?

This study can help researchers and clinicians better understand how a mother’s heart and metabolic health during pregnancy may influence a child’s long-term cardiovascular health. This highlights the potential value of early-life interventions aimed at monitoring and managing blood pressure in children with prenatal exposure to these maternal risk factors.

Who was involved?

The research included 12,480 mother-child pairs from study sites in the ECHO program. The mother's average age at pregnancy was 30 years, and 47% of participating mothers were non-White. At least one maternal cardiometabolic risk factor was present in 44% of the mothers.

What happened during the study?

Researchers gathered information about mothers’ heart and metabolic health from medical records or surveys. They also collected blood pressure readings from their children, either during study visits or from their medical records. They used statistical methods to look at how a mother’s health before and during pregnancy might be linked to her child’s blood pressure—both at the youngest age and as the child grew from age 2 to 18. They also looked at whether these links were different depending on the child’s sex or race and ethnicity.

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?

More research could help researchers understand how combinations of maternal cardiometabolic risk factors influence children’s blood pressure over time. Future studies could also examine how structural and social factors contribute to maternal health during pregnancy and shape long-term cardiovascular health in children.

Where can I learn more?

Access the full journal article, titled “Maternal cardiometabolic risk factors in pregnancy and offspring blood pressure at age 2-18 years,” 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 May 08, 2025

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Obesity, Diabetes, & High Blood Pressure Before and During Pregnancy are Associated with Higher Blood Pressure in Children

No Significant Associations Observed Between Prenatal Antibiotic Use and Wheezing Symptoms in Infants

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No Significant Associations Observed Between Prenatal Antibiotic Use and Wheezing Symptoms in Infants

Authors: Rachel Greenberg, 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?

Wheezing symptoms occur in 20-40% of infants, contributing to a substantial impact on children’s quality of life and their use of healthcare. Multiple early exposures, such as prenatal exposure to cigarette smoking, have been associated with these wheezing symptoms.

Previous studies have suggested a possible link between antibiotic exposure during pregnancy and an increased risk of wheezing and cough in children, caused by an imbalance in the birthing parent’s microbiome due to antibiotic use. However, these studies had some limitations. Additional research was needed to include enough participants to produce reliable results and account for other factors that might have influenced outcomes. This study examined the association between prenatal antibiotic exposure and the development of wheezing during infancy using a large national sample of infants and birthing parents.

What were the study results?

In this study, 36% of pregnant participants used at least one antibiotic while pregnant, and about 26% of infants had a report of wheezing. Overall, the research team observed that exposure to antibiotics during pregnancy was not associated with infant wheezing during the first 18 months after birth. Note that most outcome data were based on birthing parent/caregivers’ self-reports.

Prenatal antibiotic exposure was also not associated with an increase in emergency room visits or hospitalizations for wheeze during infancy. However, prenatal antibiotic use was associated with higher odds of medication use for wheeze or dry cough during infancy, which could imply more severe symptoms and a medical provider’s diagnosis. It is important to note that the study team found an association between prenatal antibiotic exposure and medication use for wheeze or cough during infancy only among children born via vaginal delivery and thus exposed to the birthing parent's microbiota. This finding supports the theory that a change in the microbiome of the birthing parent and infant is related to this association.

The researchers also observed an association between prenatal antibiotic exposure and wheeze in research sites that recruited participants who had a family history of asthma, suggesting that a genetic or environmental risk within these families may increase the likelihood of wheeze.

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 the study's impact?

The results of this study raise the possibility of an association between prenatal use of prenatal antibiotics and medication use for wheezing in the 18 months after birth. It suggested that prenatal antibiotics may influence respiratory outcomes during infancy, but further studies are needed to understand how the timing and type of antibiotic use may influence these effects.

Who was involved?

This study included 4,721 pregnant participants and their 4,779 infants from 12 study sites in the ECHO Cohort Consortium. Most pregnant participants were between 25 and 35 years old, non-Hispanic White, and had a college degree or more. Overall, 36% of the pregnant participants used at least one antibiotic during their pregnancy.

What happened during the study?

The study team analyzed data collected using questionnaires, interviews, or medical records to analyze associations between prenatal antibiotic exposure and airway symptoms (e.g., wheeze, cough) during infancy. The study team confined the outcome of wheezing to infancy (prior to the age when asthma is typically diagnosed), and they evaluated antibiotic exposure throughout pregnancy.

What happens next?

Future research is needed to understand how the timing and type of antibiotic use during pregnancy influences infant wheeze outcomes. Additional studies are also needed to replicate these findings, which could then lead to clinical implications.

Where can I learn more?

Access the full journal article, titled “Association Between Prenatal Antibiotic Exposure and Infant Wheeze Outcomes,” in Acta Paediatrica.

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 February 27, 2025

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No Significant Associations Observed Between Prenatal Antibiotic Use and Wheezing Symptoms in Infants

Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

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Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

Authors: Michael S. Bloom, Adaeze Wosu Nzegwu, et al.

Who sponsored this study?

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

Why was this study needed?

Exposure to endocrine-disrupting chemicals (EDCs), such as environmental phenols (EPs) and parabens, is common during pregnancy through everyday products like plastics, food packaging, and personal care items. These chemicals can cross the placenta and, despite their short breakdown time in the body, EPs are often detected in human tissue. Prenatal exposure has been linked to risks such as pregnancy complications, developmental issues, and long-term health problems, particularly in underserved populations. Low-income and minority communities may face higher exposure to chemicals like EPs due to closer proximity to factories and waste facilities, as well as limited access to a broader range of consumer products and fresh foods. This study investigated racial and ethnic differences in prenatal exposure to EPs and parabens across the U.S., addressing the limitations of earlier, smaller studies that did not fully explore these differences among pregnant women.

What were the study results?

Urinary levels of most EPs examined varied significantly by race and ethnicity, with non-Hispanic Black and Hispanic participants having higher levels of certain EPs than non-Hispanic White participants. Specifically, non-Hispanic Black and Hispanic participants had higher average levels of a chemical that comes from paradichlorobenzene in their urine compared to non-Hispanic White participants. Paradichlorobenzene is found in mothballs, fumigants, and air fresheners, and it is mainly inhaled. Non-Hispanic Black participants also had higher levels of specific parabens, which are preservatives used in processed foods and personal care products. These chemicals can be absorbed through eating or using such products.

What was this study's impact?

The study highlighted the disproportionately high levels of exposure to EPs among pregnant racial and ethnic minorities in the U.S.

Who was involved?

The study included 4,006 pregnant participants from 11 ECHO Cohort Study Sites across the U.S., representing various racial/ethnic identities, including Hispanic, non-Hispanic Black, non-Hispanic Other, and non-Hispanic White individuals.

What happened during the study?

The study analyzed 7,854 urine specimens collected during pregnancy. Researchers measured the levels of 10 different urinary EPs.

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?

Further studies could examine the sources of these exposure differences.

Where can I learn more?

Access the full journal article, titled “Racial and ethnic differences in prenatal exposure to environmental phenols and parabens in the ECHO Cohort,” in the Journal of Exposure Science and Environmental Epidemiology.

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

Published February 15, 2025

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Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

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COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

Authors: Megan Romano, et al.

Who sponsored this study?

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

Why was this study needed?

The COVID-19 pandemic caused unprecedented disruptions in the daily lives of children and families worldwide. In the United States, recommendations to stay home and wear masks may have altered people's exposure to various potential endocrine-disrupting chemicals (EDCs). For example, changes in the use of certain consumer products, such as N-95 masks, and decreased exposure to air pollutants due to lockdown may have influenced these exposures. ECHO researchers wanted to learn whether exposures during pregnancy changed during the COVID-19 pandemic.

What were the study results?

During the COVID-19 pandemic, urinary levels of certain chemicals changed, reflecting shifts in exposure. Levels of specific polycyclic aromatic hydrocarbons (PAHs), which are air pollutants from car exhaust, fire smoke, and some grilled foods, decreased. Some synthetic phenols, used in plastics and disinfectants found in household cleaners and consumer products like mouthwashes, also showed a decline. However, levels increased of certain organophosphate esters (OPEs)—chemicals used in plastics, flame retardants, and cleaning agents, and more recently in surgical, KN95, and N95 masks. - The increase in these chemicals may be linked to the use of face masks during the pandemic. When people wore masks regularly, they may have unknowingly inhaled small amounts of these chemicals, leading to higher levels in their bodies. In contrast, urinary concentrations of chemicals commonly found in plastics, personal care products, and pesticides remained largely unchanged.

What was this study's impact?

The study highlighted how significant behavioral changes during the pandemic may have contributed to changes in exposures to harmful environmental chemicals.

Who was involved?

The study included 47 participants from three ECHO Cohort Study Sites who contributed urine samples before and during the COVID-19 pandemic.

What happened during the study?

Researchers collected urine samples from participants before (between October 2018 and February 2020) and during (between March 2020 and April 2021) the COVID-19 pandemic. They tested the samples for various chemicals.

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?

Researchers could continue tracking changes in chemical exposures and their potential health effects to better understand how these environmental exposures change over time, particularly during significant societal changes like the COVID-19 pandemic.

Where can I learn more?

Access the full journal article, titled “Changes in urinary concentrations of contemporary and emerging chemicals in commerce during the COVID-19 pandemic: Insights from the Environmental influences on Child Health Outcomes (ECHO) program,” in PLoS One.

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, 2025

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COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

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

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ECHO Study Investigates Nutrition During Pregnancy and Infant Growth Outcomes

ECHO Cohort Study Finds No Significant Associations Between Prenatal Dietary Patterns and ASD Diagnosis

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ECHO Cohort Study Finds No Significant Associations Between Prenatal Dietary Patterns and ASD Diagnosis

Authors: Rachel Vecchione, Kristen Lyall, 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?

Diet during pregnancy plays a major role in fetal development. Prior research has shown associations between several dietary factors and certain neurodevelopmental conditions in children, including autism spectrum disorder (ASD). ASD is a neurodevelopmental condition that affects social communication and behaviors, and presents in a wide variety of behaviors, abilities, and challenges.

This study helped to fill gaps in understanding the relationship between maternal dietary patterns during pregnancy and ASD-related outcomes in children. Most previous studies examining links between prenatal diet and ASD and other neurodevelopmental outcomes have focused on individual foods or nutrients, rather than overall dietary patterns. Dietary patterns may be useful to examine because they summarize the usual intake of a wide range of foods and may capture combined effects across many nutrients. Dietary patterns that capture the intake of recommended foods may also help to provide clearer communication than summaries across individual nutrients. This study therefore aimed to provide a comprehensive assessment by examining several established dietary patterns and their associations with ASD-related traits and diagnoses.

What were the study results?

Dietary patterns examined in this study included the Healthy Eating Index (HEI) and the Alternative Healthy Eating Index modified for Pregnancy (AHEI-P), as well as the Empirical Dietary Inflammatory Index (EDIP). Both the HEI and AHEI-P are validated dietary patterns that are measures of overall diet quality. Higher scores on these patterns indicate better adherence to dietary guidelines. In contrast, higher scores on the EDIP indicate a more pro-inflammatory diet.

The study found that higher prenatal scores on the HEI the AHEI-P were associated with modest decreases in ASD-related traits. However, there were no significant associations between prenatal intake of these dietary patterns and ASD diagnosis. The findings suggest that while there may not be strong associations between prenatal dietary patterns and ASD diagnosis itself, there may be subtle associations with broader traits like social communication difficulties that warrant further investigation.

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 the study's impact?

This study contributes to the understanding of how prenatal diet may relate to ASD-related characteristics in children. It also highlights the need to further study the potential mechanisms linking prenatal diet to ASD-related traits and to consider broader dietary patterns in addition to individual nutrients and foods.

Who was involved?

The study included 6,084 mother-child pairs from 14 ECHO Cohort Study Sites. The participants were socioeconomically and demographically diverse, drawn from a large U.S.-wide sample, including general population sites and sites with a higher chance of ASD occurring in families.

What happened during the study?

Researchers collected data from individual sites that used Food Frequency Questionnaires to assess diet during pregnancy and enable the calculation of dietary patterns. The study examined associations between three dietary patterns and ASD-related outcomes while adjusting for potential confounding factors such as maternal age, pre-pregnancy BMI, sociodemographic factors, and child characteristics.

What happens next?

Future studies could help researchers confirm the results of this study and explore the subtle associations between prenatal diet and ASD-related traits. Further research could also examine multiple ASD-related outcomes, using larger and more diverse samples, and investigate potential mechanisms linking prenatal diet to ASD-related traits.

Where can I learn more?

Access the full journal article, titled “Maternal Dietary Patterns During Pregnancy and Child Autism-Related Traits in the Environmental influences on Child Health Outcomes Consortium,” in Nutrients.

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

Published November 6, 2024

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ECHO Cohort Study Finds No Significant Associations Between Prenatal Dietary Patterns and ASD Diagnosis

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

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

ECHO Study Investigates Pollution Exposure and Birth Outcomes in Pregnant Women Living in Historically Redlined Neighborhoods

Authors: Teresa Herrera, Akhgar Ghassabian, 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?

Exposure to tiny air pollutants known as PM2.5 during pregnancy can lead to outcomes like low birth weight and preterm birth. Factors such as weather, government policies, and social conditions can affect how much exposure pregnant women have to these pollutants. One factor that may have affected exposure is redlining, the historical practice of designating certain neighborhoods, often where minority groups lived, as risky investments for lenders. This grading system ranked neighborhoods on an A through D scale—A being the most desirable—which often led to disinvestment and lack of resources in lower-rated areas. While redlining was made illegal following the 1968 Fair Housing Act, it continues to affect the health outcomes of people living in historically redlined areas.

ECHO researchers wanted to learn whether living in historically redlined areas during pregnancy affects air pollution exposure and birth outcomes in New York City (NYC). Understanding what influences PM2.5 levels and their impact on birth outcomes can help improve the health of mothers and their children.

What were the study results?

The study found that living in lower-graded or ungraded census tracts during pregnancy was associated with higher exposure to PM2.5. These women also tended to have babies with lower birth weights. This association was strong even when considering factors such as race, ethnicity, and income at individual and community levels.

What was this study's impact?

The study supports the literature linking redlining to contemporary outcomes. This study highlights the multifaceted nature of structural racism. Findings from non-graded areas indicate that there are likely additional factors, along with redlining, that play a role in perpetuating modern-day inequality.

Who was involved?

The participants were 3,160 pregnant mothers and their babies in the NYC metropolitan area who were enrolled in six ECHO Cohort research sites. The study included pregnant mothers from 2005 to 2022 who had air pollution estimates available for their residential address. Most participants who identified as Black or White lived in neighborhoods that had been given a D grade, the lowest rating. Most participants who identified as Hispanic lived in neighborhoods with B or C grades.

What happened during the study?

Researchers used statistical methods to explore whether living in neighborhoods that were historically redlined was associated with higher exposure to air pollution (PM2.5) during pregnancy. They also examined if living in these neighborhoods was associated with the baby's birth weight, the likelihood of being born early, and the chances of having a low birth weight.

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?

The authors note that future research could look at other practices like racial exclusionary zoning to fully understand the ongoing systemic effects of redlining.

Where can I learn more?

Access the full journal article, titled “Redlining in New York City: Impacts on Particulate Matter Exposure During Pregnancy and Birth Outcomes,” in Journal of Epidemiology and Community 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 5, 2024

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ECHO Study Investigates Pollution Exposure and Birth Outcomes in Pregnant Women Living in Historically Redlined Neighborhoods